diff --git a/onnxoptimizer/passes/fuse_matmul_add_bias_into_gemm.h b/onnxoptimizer/passes/fuse_matmul_add_bias_into_gemm.h
index f3e7b6d8b..94d780533 100644
--- a/onnxoptimizer/passes/fuse_matmul_add_bias_into_gemm.h
+++ b/onnxoptimizer/passes/fuse_matmul_add_bias_into_gemm.h
@@ -93,7 +93,7 @@ struct FuseMatMulAddBiasIntoGemm final : public PredicateBasedPass {
     gemm->f_(kbeta, 1.0);
     gemm->i_(ktransA, 0);
     gemm->i_(ktransB, 0);
-    gemm->insertBefore(orig_matmul->node());
+    gemm->insertBefore(n);
     const bool replacing_success = tryReplacingAllUsesWith(n, gemm);
     if (!replacing_success) {
       return false;
diff --git a/onnxoptimizer/test/optimizer_test.py b/onnxoptimizer/test/optimizer_test.py
index 5cd6b32fd..ca969d4d2 100644
--- a/onnxoptimizer/test/optimizer_test.py
+++ b/onnxoptimizer/test/optimizer_test.py
@@ -1478,9 +1478,10 @@ def test_fuse_matmul_add_bias_into_gemm(self):  # type: () -> None
             [helper.make_tensor_value_info("A", TensorProto.FLOAT, (32, 16))],
         )
         optimized_model = self._optimized(graph, ["fuse_matmul_add_bias_into_gemm"])
+        assert len(list(optimized_model.graph.node)) == 2
+        assert optimized_model.graph.node[0].op_type == "MatMul"
+        assert optimized_model.graph.node[1].op_type == "Gemm"
 
-        assert len(list(optimized_model.graph.node)) == 1
-        assert optimized_model.graph.node[0].op_type == "Gemm"
 
     def test_fuse_matmul_add_bias_into_gemm_2d_bias(self):  # type: () -> None
         matmul = helper.make_node("MatMul", ["X", "Y"], ["Z"])
@@ -1497,8 +1498,9 @@ def test_fuse_matmul_add_bias_into_gemm_2d_bias(self):  # type: () -> None
         )
         optimized_model = self._optimized(graph, ["fuse_matmul_add_bias_into_gemm"])
 
-        assert len(list(optimized_model.graph.node)) == 1
-        assert optimized_model.graph.node[0].op_type == "Gemm"
+        assert len(list(optimized_model.graph.node)) == 2
+        assert optimized_model.graph.node[0].op_type == "MatMul"
+        assert optimized_model.graph.node[1].op_type == "Gemm"
 
     # type: () -> None
     def test_fuse_matmul_add_bias_into_gemm_2d_bias_same_shape(self):
@@ -1516,8 +1518,34 @@ def test_fuse_matmul_add_bias_into_gemm_2d_bias_same_shape(self):
         )
         optimized_model = self._optimized(graph, ["fuse_matmul_add_bias_into_gemm"])
 
-        assert len(list(optimized_model.graph.node)) == 1
-        assert optimized_model.graph.node[0].op_type == "Gemm"
+        assert len(list(optimized_model.graph.node)) == 2
+        assert optimized_model.graph.node[0].op_type == "MatMul"
+        assert optimized_model.graph.node[1].op_type == "Gemm"
+
+    def test_fuse_matmul_add_bias_into_gemm_must_keep_topological_order(self):
+        matmul = helper.make_node("MatMul", ["X", "Y"], ["Z"], name='matmul')
+        bias = helper.make_node("MatMul", ["M", "N"], ["B"], name='bias')
+        add = helper.make_node("Add", ["Z", "B"], ["A"], name='add')
+        graph = helper.make_graph(
+            [matmul, bias, add],
+            "test",
+            [
+                helper.make_tensor_value_info("X", TensorProto.FLOAT, (32, 10)),
+                helper.make_tensor_value_info("Y", TensorProto.FLOAT, (10, 16)),
+                helper.make_tensor_value_info("M", TensorProto.FLOAT, (32, 10)),
+                helper.make_tensor_value_info("N", TensorProto.FLOAT, (10, 16)),
+            ],
+            [helper.make_tensor_value_info("A", TensorProto.FLOAT, (32, 16))],
+            value_info=[
+                helper.make_tensor_value_info("B", TensorProto.FLOAT, (32, 16)),
+            ]
+        )
+        optimized_model = self._optimized(graph, ["fuse_matmul_add_bias_into_gemm"])
+
+        assert len(list(optimized_model.graph.node)) == 3
+        assert optimized_model.graph.node[0].op_type == "MatMul"
+        assert optimized_model.graph.node[1].op_type == "MatMul"
+        assert optimized_model.graph.node[2].op_type == "Gemm"
 
     # type: () -> None
     def test_fuse_matmul_add_bias_into_gemm_2d_bias_bcast_no_fuse(self):