diff --git a/paddle/fluid/operators/sampling_id_op.cc b/paddle/fluid/operators/sampling_id_op.cc
index 17f6461fcb816b23d100e8d5a61aac484c1a6ba3..d13eeabcb96fcf8c4073184bc078186eb6b5f089 100644
--- a/paddle/fluid/operators/sampling_id_op.cc
+++ b/paddle/fluid/operators/sampling_id_op.cc
@@ -30,6 +30,8 @@ class SamplingIdOp : public framework::OperatorWithKernel {
                    "Output(Out) of SamplingIdOp should not be null.");
 
     auto input_dims = ctx->GetInputDim("X");
+    PADDLE_ENFORCE(input_dims.size() == 2,
+                   "Input(X, Filter) should be 2-D tensor.");
 
     framework::DDim dims = input_dims;
     ctx->SetOutputDim("Out", dims);
@@ -46,10 +48,8 @@ class SamplingIdOpMaker : public framework::OpProtoAndCheckerMaker {
     AddOutput("Out", "SamplingId data tensor.");
     AddComment(R"DOC(
 SamplingId Operator.
-  @brief A layer for sampling id from multinomial distribution from the
- input layer. Sampling one id for one sample. The result is stored in
- output_.ids.
-)DOC");
+A layer for sampling id from multinomial distribution from the
+ input layer. Sampling one id for one sample.)DOC");
   }
 };
 }  // namespace operators