diff --git a/paddle/fluid/operators/warpctc_op.cc b/paddle/fluid/operators/warpctc_op.cc
index 7033d55a53b876fce34f91c05c0dc91288ae4a59..df9212f9c930c683045edcb56c85cd661e54f769 100644
--- a/paddle/fluid/operators/warpctc_op.cc
+++ b/paddle/fluid/operators/warpctc_op.cc
@@ -52,7 +52,7 @@ class WarpCTCOp : public framework::OperatorWithKernel {
                    sequence_width);
 
     // TODO(liuyiqun): it is tricky to set the wrong dimension here.
-    ctx->SetOutputDim("Loss", {logits_dims[0], 1});
+    ctx->SetOutputDim("Loss", {-1, 1});
   }
 
  protected: