diff --git a/apps/rpm/serializers.py b/apps/rpm/serializers.py
index dfed379c..4cb62752 100644
--- a/apps/rpm/serializers.py
+++ b/apps/rpm/serializers.py
@@ -272,7 +272,7 @@ class RpjmemberUpdateSerializer(CustomModelSerializer):
         fields = ['duty', 'is_manager', 'rcertificates']
 
     def update(self, instance, validated_data):
-        rpj = validated_data['rpj']
+        rpj = instance.rpj
         if rpj.state in [Rpj.RPJ_DONE, Rpj.RPJ_CLOSE]:
             raise ParseError('该项目状态成员不可修改')
         rcertificates = validated_data.pop('rcertificates')