diff --git a/model_zoo/official/cv/unet/eval.py b/model_zoo/official/cv/unet/eval.py
index 6b8e746c6e..f3a2cce6f4 100644
--- a/model_zoo/official/cv/unet/eval.py
+++ b/model_zoo/official/cv/unet/eval.py
@@ -25,7 +25,8 @@ from mindspore.train.serialization import load_checkpoint, load_param_into_net
 from mindspore.nn.loss.loss import _Loss
 
 from src.data_loader import create_dataset
-from src.unet import UNet
+from src.unet_medical import UNetMedical
+from src.unet_nested import NestedUNet, UNet
 from src.config import cfg_unet
 
 from scipy.special import softmax
@@ -34,8 +35,6 @@ device_id = int(os.getenv('DEVICE_ID'))
 context.set_context(mode=context.GRAPH_MODE, device_target="Ascend", save_graphs=False, device_id=device_id)
 
 
-
-
 class CrossEntropyWithLogits(_Loss):
     def __init__(self):
         super(CrossEntropyWithLogits, self).__init__()
@@ -64,10 +63,11 @@ class dice_coeff(nn.Metric):
 
     def update(self, *inputs):
         if len(inputs) != 2:
-            raise ValueError('Mean dice coeffcient need 2 inputs (y_pred, y), but got {}'.format(len(inputs)))
+            raise ValueError('Mean dice coefficient need 2 inputs (y_pred, y), but got {}'.format(len(inputs)))
 
         y_pred = self._convert_data(inputs[0])
         y = self._convert_data(inputs[1])
+
         self._samples_num += y.shape[0]
         y_pred = y_pred.transpose(0, 2, 3, 1)
         y = y.transpose(0, 2, 3, 1)
@@ -90,13 +90,20 @@ def test_net(data_dir,
              ckpt_path,
              cross_valid_ind=1,
              cfg=None):
-
-    net = UNet(n_channels=cfg['num_channels'], n_classes=cfg['num_classes'])
+    if cfg['model'] == 'unet_medical':
+        net = UNetMedical(n_channels=cfg['num_channels'], n_classes=cfg['num_classes'])
+    elif cfg['model'] == 'unet_nested':
+        net = NestedUNet(in_channel=cfg['num_channels'], n_class=cfg['num_classes'])
+    elif cfg['model'] == 'unet_simple':
+        net = UNet(in_channel=cfg['num_channels'], n_class=cfg['num_classes'])
+    else:
+        raise ValueError("Unsupported model: {}".format(cfg['model']))
     param_dict = load_checkpoint(ckpt_path)
     load_param_into_net(net, param_dict)
 
     criterion = CrossEntropyWithLogits()
-    _, valid_dataset = create_dataset(data_dir, 1, 1, False, cross_valid_ind, False)
+    _, valid_dataset = create_dataset(data_dir, 1, 1, False, cross_valid_ind, False,
+                                      do_crop=cfg['crop'], img_size=cfg['img_size'])
     model = Model(net, loss_fn=criterion, metrics={"dice_coeff": dice_coeff()})
 
     print("============== Starting Evaluating ============")
diff --git a/model_zoo/official/cv/unet/export.py b/model_zoo/official/cv/unet/export.py
index fc72b65dd8..17eb773f40 100644
--- a/model_zoo/official/cv/unet/export.py
+++ b/model_zoo/official/cv/unet/export.py
@@ -18,7 +18,8 @@ import numpy as np
 
 from mindspore import Tensor, export, load_checkpoint, load_param_into_net, context
 
-from src.unet.unet_model import UNet
+from src.unet_medical.unet_model import UNetMedical
+from src.unet_nested import NestedUNet, UNet
 from src.config import cfg_unet as cfg
 
 parser = argparse.ArgumentParser(description='unet export')
@@ -38,7 +39,14 @@ if args.device_target == "Ascend":
     context.set_context(device_id=args.device_id)
 
 if __name__ == "__main__":
-    net = UNet(n_channels=cfg["num_channels"], n_classes=cfg["num_classes"])
+    if cfg['model'] == 'unet_medical':
+        net = UNetMedical(n_channels=cfg['num_channels'], n_classes=cfg['num_classes'])
+    elif cfg['model'] == 'unet_nested':
+        net = NestedUNet(in_channel=cfg['num_channels'], n_class=cfg['num_classes'])
+    elif cfg['model'] == 'unet_simple':
+        net = UNet(in_channel=cfg['num_channels'], n_class=cfg['num_classes'])
+    else:
+        raise ValueError("Unsupported model: {}".format(cfg['model']))
     # return a parameter dict for model
     param_dict = load_checkpoint(args.ckpt_file)
     # load the parameter into net
diff --git a/model_zoo/official/cv/unet/mindspore_hub_conf.py b/model_zoo/official/cv/unet/mindspore_hub_conf.py
index 4e292980da..90955c10a5 100644
--- a/model_zoo/official/cv/unet/mindspore_hub_conf.py
+++ b/model_zoo/official/cv/unet/mindspore_hub_conf.py
@@ -13,7 +13,7 @@
 # limitations under the License.
 # ============================================================================
 """hub config."""
-from src.unet import UNet
+from src.unet_medical import UNet
 
 def create_network(name, *args, **kwargs):
     if name == "unet2d":
diff --git a/model_zoo/official/cv/unet/scripts/run_distribute_train.sh b/model_zoo/official/cv/unet/scripts/run_distribute_train.sh
index 807490db21..f00014d27f 100644
--- a/model_zoo/official/cv/unet/scripts/run_distribute_train.sh
+++ b/model_zoo/official/cv/unet/scripts/run_distribute_train.sh
@@ -14,15 +14,14 @@
 # limitations under the License.
 # ============================================================================
 
-echo "=============================================================================================================="
-echo "Please run the script as: "
-echo "bash scripts/run_distribute_train.sh [RANK_TABLE_FILE] [DATASET]"
-echo "for example: bash run_distribute_train.sh /absolute/path/to/RANK_TABLE_FILE /absolute/path/to/data"
-echo "=============================================================================================================="
-
 if [ $# != 2 ]
 then
+    echo "=============================================================================================================="
     echo "Usage: bash scripts/run_distribute_train.sh [RANK_TABLE_FILE] [DATASET]"
+    echo "Please run the script as: "
+    echo "bash scripts/run_distribute_train.sh [RANK_TABLE_FILE] [DATASET]"
+    echo "for example: bash run_distribute_train.sh /absolute/path/to/RANK_TABLE_FILE /absolute/path/to/data"
+    echo "=============================================================================================================="
     exit 1
 fi
 
diff --git a/model_zoo/official/cv/unet/scripts/run_standalone_eval.sh b/model_zoo/official/cv/unet/scripts/run_standalone_eval.sh
index 2bfccfb331..ded1f908a0 100644
--- a/model_zoo/official/cv/unet/scripts/run_standalone_eval.sh
+++ b/model_zoo/official/cv/unet/scripts/run_standalone_eval.sh
@@ -14,11 +14,14 @@
 # limitations under the License.
 # ============================================================================
 
-echo "=============================================================================================================="
-echo "Please run the script as: "
-echo "bash scripts/run_standalone_eval.sh [DATASET] [CHECKPOINT]"
-echo "for example: bash run_standalone_eval.sh /path/to/data/ /path/to/checkpoint/"
-echo "=============================================================================================================="
+if [ $# != 2 ]
+then
+    echo "=============================================================================================================="
+    echo "Please run the script as: "
+    echo "bash scripts/run_standalone_eval.sh [DATASET] [CHECKPOINT]"
+    echo "for example: bash run_standalone_eval.sh /path/to/data/ /path/to/checkpoint/"
+    echo "=============================================================================================================="
+fi
 
 export DEVICE_ID=0
 python eval.py --data_url=$1 --ckpt_path=$2 > eval.log 2>&1 &
\ No newline at end of file
diff --git a/model_zoo/official/cv/unet/scripts/run_standalone_train.sh b/model_zoo/official/cv/unet/scripts/run_standalone_train.sh
index 3a1594d51f..c8089b5a2b 100644
--- a/model_zoo/official/cv/unet/scripts/run_standalone_train.sh
+++ b/model_zoo/official/cv/unet/scripts/run_standalone_train.sh
@@ -14,11 +14,14 @@
 # limitations under the License.
 # ============================================================================
 
-echo "=============================================================================================================="
-echo "Please run the script as: "
-echo "bash scripts/run_standalone_train.sh [DATASET]"
-echo "for example: bash run_standalone_train.sh /path/to/data/"
-echo "=============================================================================================================="
+if [ $# != 1 ]
+then
+    echo "=============================================================================================================="
+    echo "Please run the script as: "
+    echo "bash scripts/run_standalone_train.sh [DATASET]"
+    echo "for example: bash run_standalone_train.sh /path/to/data/"
+    echo "=============================================================================================================="
+fi
 
 export DEVICE_ID=0
 python train.py --data_url=$1 > train.log 2>&1 &
\ No newline at end of file
diff --git a/model_zoo/official/cv/unet/src/config.py b/model_zoo/official/cv/unet/src/config.py
index 9f8eba7b45..2e34a7bd6e 100644
--- a/model_zoo/official/cv/unet/src/config.py
+++ b/model_zoo/official/cv/unet/src/config.py
@@ -13,7 +13,10 @@
 # limitations under the License.
 # ============================================================================
 
-cfg_unet = {
+cfg_unet_medical = {
+    'model': 'unet_medical',
+    'crop': [388 / 572, 388 / 572],
+    'img_size': [572, 572],
     'lr': 0.0001,
     'epochs': 400,
     'distribute_epochs': 1600,
@@ -30,3 +33,47 @@ cfg_unet = {
     'resume': False,
     'resume_ckpt': './',
 }
+
+cfg_unet_nested = {
+    'model': 'unet_nested',
+    'crop': None,
+    'img_size': [576, 576],
+    'lr': 0.0001,
+    'epochs': 400,
+    'distribute_epochs': 1600,
+    'batchsize': 16,
+    'cross_valid_ind': 1,
+    'num_classes': 2,
+    'num_channels': 1,
+
+    'keep_checkpoint_max': 10,
+    'weight_decay': 0.0005,
+    'loss_scale': 1024.0,
+    'FixedLossScaleManager': 1024.0,
+
+    'resume': False,
+    'resume_ckpt': './',
+}
+
+cfg_unet_simple = {
+    'model': 'unet_simple',
+    'crop': None,
+    'img_size': [576, 576],
+    'lr': 0.0001,
+    'epochs': 400,
+    'distribute_epochs': 1600,
+    'batchsize': 16,
+    'cross_valid_ind': 1,
+    'num_classes': 2,
+    'num_channels': 1,
+
+    'keep_checkpoint_max': 10,
+    'weight_decay': 0.0005,
+    'loss_scale': 1024.0,
+    'FixedLossScaleManager': 1024.0,
+
+    'resume': False,
+    'resume_ckpt': './',
+}
+
+cfg_unet = cfg_unet_medical
diff --git a/model_zoo/official/cv/unet/src/data_loader.py b/model_zoo/official/cv/unet/src/data_loader.py
index dbf5b664cf..32f056628e 100644
--- a/model_zoo/official/cv/unet/src/data_loader.py
+++ b/model_zoo/official/cv/unet/src/data_loader.py
@@ -82,7 +82,8 @@ def train_data_augmentation(img, mask):
     return img, mask
 
 
-def create_dataset(data_dir, repeat=400, train_batch_size=16, augment=False, cross_val_ind=1, run_distribute=False):
+def create_dataset(data_dir, repeat=400, train_batch_size=16, augment=False, cross_val_ind=1, run_distribute=False,
+                   do_crop=None, img_size=None):
 
     images = _load_multipage_tiff(os.path.join(data_dir, 'train-volume.tif'))
     masks = _load_multipage_tiff(os.path.join(data_dir, 'train-labels.tif'))
@@ -121,8 +122,12 @@ def create_dataset(data_dir, repeat=400, train_batch_size=16, augment=False, cro
     ds_valid_images = ds.NumpySlicesDataset(data=valid_image_data, sampler=None, shuffle=False)
     ds_valid_masks = ds.NumpySlicesDataset(data=valid_mask_data, sampler=None, shuffle=False)
 
-    c_resize_op = c_vision.Resize(size=(388, 388), interpolation=Inter.BILINEAR)
-    c_pad = c_vision.Pad(padding=92)
+    if do_crop:
+        resize_size = [int(img_size[x] * do_crop[x]) for x in range(len(img_size))]
+    else:
+        resize_size = img_size
+    c_resize_op = c_vision.Resize(size=(resize_size[0], resize_size[1]), interpolation=Inter.BILINEAR)
+    c_pad = c_vision.Pad(padding=(img_size[0] - resize_size[0]) // 2)
     c_rescale_image = c_vision.Rescale(1.0/127.5, -1)
     c_rescale_mask = c_vision.Rescale(1.0/255.0, 0)
 
@@ -136,12 +141,13 @@ def create_dataset(data_dir, repeat=400, train_batch_size=16, augment=False, cro
     train_ds = train_ds.project(columns=["image", "mask"])
     if augment:
         augment_process = train_data_augmentation
-        c_resize_op = c_vision.Resize(size=(572, 572), interpolation=Inter.BILINEAR)
+        c_resize_op = c_vision.Resize(size=(img_size[0], img_size[1]), interpolation=Inter.BILINEAR)
         train_ds = train_ds.map(input_columns=["image", "mask"], operations=augment_process)
         train_ds = train_ds.map(input_columns="image", operations=c_resize_op)
         train_ds = train_ds.map(input_columns="mask", operations=c_resize_op)
 
-    train_ds = train_ds.map(input_columns="mask", operations=c_center_crop)
+    if do_crop:
+        train_ds = train_ds.map(input_columns="mask", operations=c_center_crop)
     post_process = data_post_process
     train_ds = train_ds.map(input_columns=["image", "mask"], operations=post_process)
     train_ds = train_ds.shuffle(repeat*24)
@@ -151,7 +157,8 @@ def create_dataset(data_dir, repeat=400, train_batch_size=16, augment=False, cro
     valid_mask_ds = ds_valid_masks.map(input_columns="mask", operations=c_trans_normalize_mask)
     valid_ds = ds.zip((valid_image_ds, valid_mask_ds))
     valid_ds = valid_ds.project(columns=["image", "mask"])
-    valid_ds = valid_ds.map(input_columns="mask", operations=c_center_crop)
+    if do_crop:
+        valid_ds = valid_ds.map(input_columns="mask", operations=c_center_crop)
     post_process = data_post_process
     valid_ds = valid_ds.map(input_columns=["image", "mask"], operations=post_process)
     valid_ds = valid_ds.batch(batch_size=1, drop_remainder=True)
diff --git a/model_zoo/official/cv/unet/src/unet/__init__.py b/model_zoo/official/cv/unet/src/unet_medical/__init__.py
similarity index 94%
rename from model_zoo/official/cv/unet/src/unet/__init__.py
rename to model_zoo/official/cv/unet/src/unet_medical/__init__.py
index de5b46ac43..da537aac8b 100644
--- a/model_zoo/official/cv/unet/src/unet/__init__.py
+++ b/model_zoo/official/cv/unet/src/unet_medical/__init__.py
@@ -13,4 +13,4 @@
 # limitations under the License.
 # ============================================================================
 
-from .unet_model import UNet
+from .unet_model import UNetMedical
diff --git a/model_zoo/official/cv/unet/src/unet/unet_model.py b/model_zoo/official/cv/unet/src/unet_medical/unet_model.py
similarity index 90%
rename from model_zoo/official/cv/unet/src/unet/unet_model.py
rename to model_zoo/official/cv/unet/src/unet_medical/unet_model.py
index 2949d51cab..26d5f271c6 100644
--- a/model_zoo/official/cv/unet/src/unet/unet_model.py
+++ b/model_zoo/official/cv/unet/src/unet_medical/unet_model.py
@@ -13,12 +13,12 @@
 # limitations under the License.
 # ============================================================================
 
-from src.unet.unet_parts import DoubleConv, Down, Up1, Up2, Up3, Up4, OutConv
+from src.unet_medical.unet_parts import DoubleConv, Down, Up1, Up2, Up3, Up4, OutConv
 import mindspore.nn as nn
 
-class UNet(nn.Cell):
+class UNetMedical(nn.Cell):
     def __init__(self, n_channels, n_classes):
-        super(UNet, self).__init__()
+        super(UNetMedical, self).__init__()
         self.n_channels = n_channels
         self.n_classes = n_classes
         self.inc = DoubleConv(n_channels, 64)
diff --git a/model_zoo/official/cv/unet/src/unet/unet_parts.py b/model_zoo/official/cv/unet/src/unet_medical/unet_parts.py
similarity index 100%
rename from model_zoo/official/cv/unet/src/unet/unet_parts.py
rename to model_zoo/official/cv/unet/src/unet_medical/unet_parts.py
diff --git a/model_zoo/official/cv/unet/src/unet_nested/__init__.py b/model_zoo/official/cv/unet/src/unet_nested/__init__.py
new file mode 100644
index 0000000000..6a392415be
--- /dev/null
+++ b/model_zoo/official/cv/unet/src/unet_nested/__init__.py
@@ -0,0 +1,16 @@
+# Copyright 2021 Huawei Technologies Co., Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# less required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ============================================================================
+
+from .unet_model import NestedUNet, UNet
diff --git a/model_zoo/official/cv/unet/src/unet_nested/unet_model.py b/model_zoo/official/cv/unet/src/unet_nested/unet_model.py
new file mode 100644
index 0000000000..bbfba469db
--- /dev/null
+++ b/model_zoo/official/cv/unet/src/unet_nested/unet_model.py
@@ -0,0 +1,146 @@
+# Copyright 2021 Huawei Technologies Co., Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# less required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ============================================================================
+
+# Model of UnetPlusPlus
+
+import mindspore.nn as nn
+from .unet_parts import UnetConv2d, UnetUp
+
+
+class NestedUNet(nn.Cell):
+    """
+    Nested unet
+    """
+    def __init__(self, in_channel, n_class=2, feature_scale=2, use_deconv=True, use_bn=True, use_ds=True):
+        super(NestedUNet, self).__init__()
+        self.in_channel = in_channel
+        self.n_class = n_class
+        self.feature_scale = feature_scale
+        self.use_deconv = use_deconv
+        self.use_bn = use_bn
+        self.use_ds = use_ds
+
+        filters = [64, 128, 256, 512, 1024]
+        filters = [int(x / self.feature_scale) for x in filters]
+
+        # Down Sample
+        self.maxpool = nn.MaxPool2d(kernel_size=2, stride=2, pad_mode="same")
+        self.conv00 = UnetConv2d(self.in_channel, filters[0], self.use_bn)
+        self.conv10 = UnetConv2d(filters[0], filters[1], self.use_bn)
+        self.conv20 = UnetConv2d(filters[1], filters[2], self.use_bn)
+        self.conv30 = UnetConv2d(filters[2], filters[3], self.use_bn)
+        self.conv40 = UnetConv2d(filters[3], filters[4], self.use_bn)
+
+        # Up Sample
+        self.up_concat01 = UnetUp(filters[1], filters[0], self.use_deconv, 2)
+        self.up_concat11 = UnetUp(filters[2], filters[1], self.use_deconv, 2)
+        self.up_concat21 = UnetUp(filters[3], filters[2], self.use_deconv, 2)
+        self.up_concat31 = UnetUp(filters[4], filters[3], self.use_deconv, 2)
+
+        self.up_concat02 = UnetUp(filters[1], filters[0], self.use_deconv, 3)
+        self.up_concat12 = UnetUp(filters[2], filters[1], self.use_deconv, 3)
+        self.up_concat22 = UnetUp(filters[3], filters[2], self.use_deconv, 3)
+
+        self.up_concat03 = UnetUp(filters[1], filters[0], self.use_deconv, 4)
+        self.up_concat13 = UnetUp(filters[2], filters[1], self.use_deconv, 4)
+
+        self.up_concat04 = UnetUp(filters[1], filters[0], self.use_deconv, 5)
+
+        # Finale Convolution
+        self.final1 = nn.Conv2d(filters[0], n_class, 1)
+        self.final2 = nn.Conv2d(filters[0], n_class, 1)
+        self.final3 = nn.Conv2d(filters[0], n_class, 1)
+        self.final4 = nn.Conv2d(filters[0], n_class, 1)
+
+    def construct(self, inputs):
+        x00 = self.conv00(inputs)                   # channel = filters[0]
+        x10 = self.conv10(self.maxpool(x00))        # channel = filters[1]
+        x20 = self.conv20(self.maxpool(x10))        # channel = filters[2]
+        x30 = self.conv30(self.maxpool(x20))        # channel = filters[3]
+        x40 = self.conv40(self.maxpool(x30))        # channel = filters[4]
+
+        x01 = self.up_concat01(x10, x00)            # channel = filters[0]
+        x11 = self.up_concat11(x20, x10)            # channel = filters[1]
+        x21 = self.up_concat21(x30, x20)            # channel = filters[2]
+        x31 = self.up_concat31(x40, x30)            # channel = filters[3]
+
+        x02 = self.up_concat02(x11, x00, x01)       # channel = filters[0]
+        x12 = self.up_concat12(x21, x10, x11)       # channel = filters[1]
+        x22 = self.up_concat22(x31, x20, x21)       # channel = filters[2]
+
+        x03 = self.up_concat03(x12, x00, x01, x02)  # channel = filters[0]
+        x13 = self.up_concat13(x22, x10, x11, x12)  # channel = filters[1]
+
+        x04 = self.up_concat04(x13, x00, x01, x02, x03) # channel = filters[0]
+
+        final1 = self.final1(x01)
+        final2 = self.final1(x02)
+        final3 = self.final1(x03)
+        final4 = self.final1(x04)
+
+        final = (final1 + final2 + final3 + final4) / 4.0
+
+        if self.use_ds:
+            return final
+        return final4
+
+
+class UNet(nn.Cell):
+    """
+    Simple UNet with skip connection
+    """
+    def __init__(self, in_channel, n_class=2, feature_scale=2, use_deconv=True, use_bn=True):
+        super(UNet, self).__init__()
+        self.in_channel = in_channel
+        self.n_class = n_class
+        self.feature_scale = feature_scale
+        self.use_deconv = use_deconv
+        self.use_bn = use_bn
+
+        filters = [64, 128, 256, 512, 1024]
+        filters = [int(x / self.feature_scale) for x in filters]
+
+        # Down Sample
+        self.maxpool = nn.MaxPool2d(kernel_size=2, stride=2, pad_mode="same")
+        self.conv0 = UnetConv2d(self.in_channel, filters[0], self.use_bn)
+        self.conv1 = UnetConv2d(filters[0], filters[1], self.use_bn)
+        self.conv2 = UnetConv2d(filters[1], filters[2], self.use_bn)
+        self.conv3 = UnetConv2d(filters[2], filters[3], self.use_bn)
+        self.conv4 = UnetConv2d(filters[3], filters[4], self.use_bn)
+
+        # Up Sample
+        self.up_concat1 = UnetUp(filters[1], filters[0], self.use_deconv, 2)
+        self.up_concat2 = UnetUp(filters[2], filters[1], self.use_deconv, 2)
+        self.up_concat3 = UnetUp(filters[3], filters[2], self.use_deconv, 2)
+        self.up_concat4 = UnetUp(filters[4], filters[3], self.use_deconv, 2)
+
+        # Finale Convolution
+        self.final = nn.Conv2d(filters[0], n_class, 1)
+
+    def construct(self, inputs):
+        x0 = self.conv0(inputs)                   # channel = filters[0]
+        x1 = self.conv1(self.maxpool(x0))        # channel = filters[1]
+        x2 = self.conv2(self.maxpool(x1))        # channel = filters[2]
+        x3 = self.conv3(self.maxpool(x2))        # channel = filters[3]
+        x4 = self.conv4(self.maxpool(x3))        # channel = filters[4]
+
+        up4 = self.up_concat4(x4, x3)
+        up3 = self.up_concat3(up4, x2)
+        up2 = self.up_concat2(up3, x1)
+        up1 = self.up_concat1(up2, x0)
+
+        final = self.final(up1)
+
+        return final
diff --git a/model_zoo/official/cv/unet/src/unet_nested/unet_parts.py b/model_zoo/official/cv/unet/src/unet_nested/unet_parts.py
new file mode 100644
index 0000000000..8c072a24b8
--- /dev/null
+++ b/model_zoo/official/cv/unet/src/unet_nested/unet_parts.py
@@ -0,0 +1,81 @@
+# Copyright 2021 Huawei Technologies Co., Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# less required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ============================================================================
+
+""" Parts of the U-Net-PlusPlus model """
+
+import mindspore.nn as nn
+import mindspore.ops.functional as F
+import mindspore.ops.operations as P
+
+
+def conv_bn_relu(in_channel, out_channel, use_bn=True, kernel_size=3, stride=1, pad_mode="same", activation='relu'):
+    output = []
+    output.append(nn.Conv2d(in_channel, out_channel, kernel_size, stride, pad_mode=pad_mode))
+    if use_bn:
+        output.append(nn.BatchNorm2d(out_channel))
+    if activation:
+        output.append(nn.get_activation(activation))
+    return nn.SequentialCell(output)
+
+
+class UnetConv2d(nn.Cell):
+    """
+    Convolution block in Unet, usually double conv.
+    """
+    def __init__(self, in_channel, out_channel, use_bn=True, num_layer=2, kernel_size=3, stride=1, padding='same'):
+        super(UnetConv2d, self).__init__()
+        self.num_layer = num_layer
+        self.kernel_size = kernel_size
+        self.stride = stride
+        self.padding = padding
+        self.in_channel = in_channel
+        self.out_channel = out_channel
+
+        convs = []
+        for _ in range(num_layer):
+            convs.append(conv_bn_relu(in_channel, out_channel, use_bn, kernel_size, stride, padding, "relu"))
+            in_channel = out_channel
+
+        self.convs = nn.SequentialCell(convs)
+
+    def construct(self, inputs):
+        x = self.convs(inputs)
+        return x
+
+
+class UnetUp(nn.Cell):
+    """
+    Upsampling high_feature with factor=2 and concat with low feature
+    """
+    def __init__(self, in_channel, out_channel, use_deconv, n_concat=2):
+        super(UnetUp, self).__init__()
+        self.conv = UnetConv2d(in_channel + (n_concat - 2) * out_channel, out_channel, False)
+        self.concat = P.Concat(axis=1)
+        self.use_deconv = use_deconv
+        if use_deconv:
+            self.up_conv = nn.Conv2dTranspose(in_channel, out_channel, kernel_size=2, stride=2, pad_mode="same")
+        else:
+            self.up_conv = nn.Conv2d(in_channel, out_channel, 1)
+
+    def construct(self, high_feature, *low_feature):
+        if self.use_deconv:
+            output = self.up_conv(high_feature)
+        else:
+            _, _, h, w = F.shape(high_feature)
+            output = P.ResizeBilinear((h * 2, w * 2))(high_feature)
+            output = self.up_conv(output)
+        for feature in low_feature:
+            output = self.concat((output, feature))
+        return self.conv(output)
diff --git a/model_zoo/official/cv/unet/src/utils.py b/model_zoo/official/cv/unet/src/utils.py
index 8be84a1680..d6bb9d653b 100644
--- a/model_zoo/official/cv/unet/src/utils.py
+++ b/model_zoo/official/cv/unet/src/utils.py
@@ -15,6 +15,7 @@
 
 import time
 import numpy as np
+from PIL import Image
 from mindspore.train.callback import Callback
 from mindspore.common.tensor import Tensor
 
@@ -53,3 +54,6 @@ class StepLossTimeMonitor(Callback):
         if self._per_print_times != 0 and cb_params.cur_step_num % self._per_print_times == 0:
             # TEST
             print("step: %s, loss is %s, fps is %s" % (cur_step_in_epoch, loss, step_fps), flush=True)
+
+def mask_to_image(mask):
+    return Image.fromarray((mask * 255).astype(np.uint8))
diff --git a/model_zoo/official/cv/unet/train.py b/model_zoo/official/cv/unet/train.py
index dedc94899e..37615f7003 100644
--- a/model_zoo/official/cv/unet/train.py
+++ b/model_zoo/official/cv/unet/train.py
@@ -26,7 +26,8 @@ from mindspore.train.callback import CheckpointConfig, ModelCheckpoint
 from mindspore.context import ParallelMode
 from mindspore.train.serialization import load_checkpoint, load_param_into_net
 
-from src.unet import UNet
+from src.unet_medical import UNetMedical
+from src.unet_nested import NestedUNet, UNet
 from src.data_loader import create_dataset
 from src.loss import CrossEntropyWithLogits
 from src.utils import StepLossTimeMonitor
@@ -53,14 +54,23 @@ def train_net(data_dir,
         context.set_auto_parallel_context(parallel_mode=parallel_mode,
                                           device_num=group_size,
                                           gradients_mean=False)
-    net = UNet(n_channels=cfg['num_channels'], n_classes=cfg['num_classes'])
+
+    if cfg['model'] == 'unet_medical':
+        net = UNetMedical(n_channels=cfg['num_channels'], n_classes=cfg['num_classes'])
+    elif cfg['model'] == 'unet_nested':
+        net = NestedUNet(in_channel=cfg['num_channels'], n_class=cfg['num_classes'])
+    elif cfg['model'] == 'unet_simple':
+        net = UNet(in_channel=cfg['num_channels'], n_class=cfg['num_classes'])
+    else:
+        raise ValueError("Unsupported model: {}".format(cfg['model']))
 
     if cfg['resume']:
         param_dict = load_checkpoint(cfg['resume_ckpt'])
         load_param_into_net(net, param_dict)
 
     criterion = CrossEntropyWithLogits()
-    train_dataset, _ = create_dataset(data_dir, epochs, batch_size, True, cross_valid_ind, run_distribute)
+    train_dataset, _ = create_dataset(data_dir, epochs, batch_size, True, cross_valid_ind, run_distribute, cfg["crop"],
+                                      cfg['img_size'])
     train_data_size = train_dataset.get_dataset_size()
     print("dataset length is:", train_data_size)
     ckpt_config = CheckpointConfig(save_checkpoint_steps=train_data_size,