diff --git a/paddle/phi/infermeta/ternary.cc b/paddle/phi/infermeta/ternary.cc
index 013a58e30ed4c09a1071db157c2425e83fcbb7c5..0d91f7965485f36f8afa9ca2242d66fc5f48cbb1 100644
--- a/paddle/phi/infermeta/ternary.cc
+++ b/paddle/phi/infermeta/ternary.cc
@@ -814,7 +814,7 @@ void MultiClassNMSInferMeta(const MetaTensor& bboxes,
 
   out->set_dims(phi::make_ddim({-1, box_dims[2] + 2}));
   out->set_dtype(bboxes.dtype());
-  index->set_dims(phi::make_ddim({-1, box_dims[2] + 2}));
+  index->set_dims(phi::make_ddim({-1, 1}));
   index->set_dtype(DataType::INT32);
   nms_rois_num->set_dims(phi::make_ddim({-1}));
   nms_rois_num->set_dtype(DataType::INT32);