diff --git a/pyinfinitensor/src/pyinfinitensor/onnx.py b/pyinfinitensor/src/pyinfinitensor/onnx.py
index c66995d2..9d7a4a2d 100644
--- a/pyinfinitensor/src/pyinfinitensor/onnx.py
+++ b/pyinfinitensor/src/pyinfinitensor/onnx.py
@@ -32,6 +32,25 @@ def from_onnx(model: onnx.ModelProto):
                 None,
                 backend.ActType.Linear,
             )
+        elif node.op_type == "Gemm":
+            attributes = _parse_attribute(
+                node, {"alpha": 1.0, "beta": 1.0, "transA": 0, "transB": 0}
+            )
+            (alpha, beta, transA, transB) = (
+                attributes[name] for name in ["alpha", "beta", "transA", "transB"]
+            )
+            # TODO 不支持这些参数
+            assert alpha == 1.0
+            assert beta == 1.0
+            tensors[node.output[0]] = handler.matmul(
+                tensors[node.input[0]],
+                tensors[node.input[1]],
+                tensors.get(node.output[0]),
+                transA == 1,
+                transB == 1,
+                tensors[node.input[2]] if len(node.input) > 2 else None,
+                backend.ActType.Linear,
+            )
         elif node.op_type == "BatchNormalization":
             (input, mean, var, scale, bias) = (
                 tensors[node.input[i]] for i in [0, 3, 4, 1, 2]
diff --git a/pyinfinitensor/tests/test_onnx.py b/pyinfinitensor/tests/test_onnx.py
index 4f86cd8d..150ce3af 100644
--- a/pyinfinitensor/tests/test_onnx.py
+++ b/pyinfinitensor/tests/test_onnx.py
@@ -37,10 +37,18 @@ class TestStringMethods(unittest.TestCase):
     def test_matmul(self):
         x = make_tensor_value_info("x", TensorProto.FLOAT, [1, 2, 3])
         a = make_tensor_value_info("a", TensorProto.FLOAT, [1, 3, 4])
-        xa = make_tensor_value_info("b", TensorProto.FLOAT, [1, 2, 4])
+        xa = make_tensor_value_info("xa", TensorProto.FLOAT, [1, 2, 4])
         matmul = make_node("MatMul", ["x", "a"], ["xa"], name="matmul")
         make_and_import_model(make_graph([matmul], "matmul", [x, a], [xa]))
 
+    def test_gemm(self):
+        a = make_tensor_value_info("a", TensorProto.FLOAT, [1, 2, 3])
+        b = make_tensor_value_info("b", TensorProto.FLOAT, [1, 4, 3])
+        c = make_tensor_value_info("c", TensorProto.FLOAT, [1, 2, 4])
+        y = make_tensor_value_info("y", TensorProto.FLOAT, [1, 2, 4])
+        gemm = make_node("Gemm", ["a", "b", "c"], ["y"], transB=1, name="gemm")
+        make_and_import_model(make_graph([gemm], "gemm", [a, b, c], [y]))
+
     def test_batch_norm(self):
         x = make_tensor_value_info("x", TensorProto.UINT32, [1, 3, 2, 2])
         scale = make_tensor_value_info("scale", TensorProto.FLOAT, [1, 3, 1, 1])
diff --git a/src/core/operator.cc b/src/core/operator.cc
index b8e69af8..51568f8f 100644
--- a/src/core/operator.cc
+++ b/src/core/operator.cc
@@ -6,8 +6,8 @@ namespace infini {
 
 OperatorObj::OperatorObj(OpType opType, TensorVec inputs, TensorVec outputs)
     : type(opType), inputs(inputs), outputs(outputs) {
-    for (auto &t : inputs)
-        IT_ASSERT(t != nullptr);
+    for (const auto &t : inputs)
+        IT_ASSERT(t);
 }
 
 bool OperatorObj::isLinearOp() const {