diff --git a/onnxscript/rewriter/rules/common/_fuse_pad_into_conv.py b/onnxscript/rewriter/rules/common/_fuse_pad_into_conv.py
index 39aab00eda..f4daf5d2f2 100644
--- a/onnxscript/rewriter/rules/common/_fuse_pad_into_conv.py
+++ b/onnxscript/rewriter/rules/common/_fuse_pad_into_conv.py
@@ -147,6 +147,9 @@ def check(self, context, x: ir.Value, pad: ir.Value, conv: ir.Value) -> orp.Matc
         if np.any(self._pads_list[:2] + self._pads_list[x_rank : x_rank + 2]):
             self._pads_list = None
             return check_result.fail(f"{pads.name} must be zero in non-spatial dimensions.")
+        if any(p < 0 for p in self._pads_list):
+            self._pads_list = None
+            return check_result.fail(f"{pads.name} must not contain negative values.")
 
         return check_result
 
diff --git a/onnxscript/rewriter/rules/common/_fuse_pad_into_conv_test.py b/onnxscript/rewriter/rules/common/_fuse_pad_into_conv_test.py
index ded57fe023..529198fda4 100644
--- a/onnxscript/rewriter/rules/common/_fuse_pad_into_conv_test.py
+++ b/onnxscript/rewriter/rules/common/_fuse_pad_into_conv_test.py
@@ -193,6 +193,14 @@ def test_fuse_pad_into_conv(self, pad_pads, const_value, axes, conv_pads, conv_a
                 "VALID",
                 "auto_pad must be 'NOTSET'.",
             ),
+            (
+                "constant",
+                ir.tensor([0, 0, -1, -1, -1, 0, 0, 0, 0, 0], name="pads"),
+                None,
+                None,
+                "NOTSET",
+                "must not contain negative values",
+            ),
         ]
     )
     def test_unsupported_fuse_pad_into_conv(