diff --git a/mindspore/core/abstract/abstract_value.h b/mindspore/core/abstract/abstract_value.h
index f9bf8f84ba7bdf4fea21383668adf993534ff7a9..b66e5a9c3f96145e4dd3021f1cf81f4b3d132a67 100644
--- a/mindspore/core/abstract/abstract_value.h
+++ b/mindspore/core/abstract/abstract_value.h
@@ -563,7 +563,9 @@ class AbstractRefKey : public AbstractBase {
   }
   inline void set_value(const ValuePtr &value) {
     AbstractBase::set_value(value);
-    ref_key_value_ = value->cast<RefKeyPtr>();
+    if (value != nullptr) {
+      ref_key_value_ = value->cast<RefKeyPtr>();
+    }
   }
   RefKeyPtr ref_key_value() const { return ref_key_value_; }
   AbstractBasePtr Join(const AbstractBasePtr &other) override;