diff --git a/tools/onnx/onnx2ncnn.cpp b/tools/onnx/onnx2ncnn.cpp
index 7b687d192..2743c9285 100644
--- a/tools/onnx/onnx2ncnn.cpp
+++ b/tools/onnx/onnx2ncnn.cpp
@@ -3775,7 +3775,7 @@ int main(int argc, char** argv)
                 }
                 else if (attr.type() == 2)
                 {
-                    fprintf(stderr, "  # %s=%lld\n", attr.name().c_str(), attr.i());
+                    fprintf(stderr, "  # %s=%lld\n", attr.name().c_str(), (long long)attr.i());
                 }
                 else if (attr.type() == 3)
                 {