diff --git a/src/opr/impl/dnn/roi_align.cpp b/src/opr/impl/dnn/roi_align.cpp
index 3c29417ff72b1f29c55434f498f3bf9b4c6dc77e..e89ec8dcdd65f1c50d71b3bc54072f86ecc6cd23 100644
--- a/src/opr/impl/dnn/roi_align.cpp
+++ b/src/opr/impl/dnn/roi_align.cpp
@@ -42,9 +42,6 @@ SymbolVar ROIAlignForward::make(SymbolVar src, SymbolVar rois,
 
 #ifdef MGB_ENABLE_GRAD
 MGB_IMPL_OPR_GRAD(ROIAlignForward) {
-    if (out_grad[1]) {
-        return InvalidGrad::make(opr, wrt_idx);
-    }
     if (wrt_idx == 0) {
         // wrt src
         SymbolVar grad =
diff --git a/src/opr/impl/dnn/roi_pooling.cpp b/src/opr/impl/dnn/roi_pooling.cpp
index ab2801d55d054e108df4c789145673fbcae5707b..7c2d3df9e25e46717de9608d83780c8817821ad7 100644
--- a/src/opr/impl/dnn/roi_pooling.cpp
+++ b/src/opr/impl/dnn/roi_pooling.cpp
@@ -86,7 +86,7 @@ size_t ROIPoolingForward::get_workspace_size_bytes(
 
 #ifdef MGB_ENABLE_GRAD
 MGB_IMPL_OPR_GRAD(ROIPoolingForward) {
-    if (out_grad[1] || wrt_idx == 2) {
+    if (wrt_idx == 2) {
         return InvalidGrad::make(opr, wrt_idx);
     }
     if (wrt_idx == 0) {