diff --git a/src/base/smooth_l1_loss_backward.h b/src/base/smooth_l1_loss_backward.h
new file mode 100644
index 00000000..e082c388
--- /dev/null
+++ b/src/base/smooth_l1_loss_backward.h
@@ -0,0 +1,67 @@
+#ifndef INFINI_OPS_BASE_SMOOTH_L1_LOSS_BACKWARD_H_
+#define INFINI_OPS_BASE_SMOOTH_L1_LOSS_BACKWARD_H_
+
+#include "operator.h"
+
+namespace infini::ops {
+
+class SmoothL1LossBackward : public Operator<SmoothL1LossBackward> {
+ public:
+  SmoothL1LossBackward(const Tensor grad_output, const Tensor input,
+                       const Tensor target, const int64_t reduction,
+                       const double beta, Tensor grad_input)
+      : grad_output_shape_{grad_output.shape()},
+        grad_output_strides_{grad_output.strides()},
+        grad_output_type_{grad_output.dtype()},
+        input_shape_{input.shape()},
+        input_strides_{input.strides()},
+        input_type_{input.dtype()},
+        target_shape_{target.shape()},
+        target_strides_{target.strides()},
+        target_type_{target.dtype()},
+        grad_input_shape_{grad_input.shape()},
+        grad_input_strides_{grad_input.strides()},
+        grad_input_type_{grad_input.dtype()},
+        reduction_{reduction},
+        beta_{beta},
+        device_index_{grad_input.device().index()} {}
+
+  virtual void operator()(const Tensor grad_output, const Tensor input,
+                          const Tensor target, const int64_t reduction,
+                          const double beta, Tensor grad_input) const = 0;
+
+ protected:
+  Tensor::Shape grad_output_shape_;
+
+  Tensor::Strides grad_output_strides_;
+
+  DataType grad_output_type_;
+
+  Tensor::Shape input_shape_;
+
+  Tensor::Strides input_strides_;
+
+  DataType input_type_;
+
+  Tensor::Shape target_shape_;
+
+  Tensor::Strides target_strides_;
+
+  DataType target_type_;
+
+  Tensor::Shape grad_input_shape_;
+
+  Tensor::Strides grad_input_strides_;
+
+  DataType grad_input_type_;
+
+  int64_t reduction_{};
+
+  double beta_{};
+
+  int device_index_{0};
+};
+
+}  // namespace infini::ops
+
+#endif