diff --git a/ppdet/modeling/losses/iou_loss.py b/ppdet/modeling/losses/iou_loss.py
index 624cd47c0760974a5af8c9011c113efa8133d9e0..d62dd861622dcd8b30f773188525ac2de70284c2 100644
--- a/ppdet/modeling/losses/iou_loss.py
+++ b/ppdet/modeling/losses/iou_loss.py
@@ -235,4 +235,5 @@ class IouLoss(object):
             dtype=numpy_array.dtype,
             default_initializer=NumpyArrayInitializer(numpy_array))
         paddle_array.stop_gradient = True
+        paddle_array.persistable = False
         return paddle_array