diff --git a/metagpt/memory/brain_memory.py b/metagpt/memory/brain_memory.py
index e65459f1a..39e2ec43d 100644
--- a/metagpt/memory/brain_memory.py
+++ b/metagpt/memory/brain_memory.py
@@ -183,7 +183,8 @@ class BrainMemory(pydantic.BaseModel):
                 break
             msgs.append(i)
             total_length += delta
-        self.history = msgs.reverse()
+        msgs.reverse()
+        self.history = msgs
         self.is_dirty = True
         await self.dumps(redis_key=CONFIG.REDIS_KEY, redis_conf=CONFIG.REDIS_CONF)
         self.is_dirty = False