diff --git a/nonebot/adapters/_base.py b/nonebot/adapters/_base.py
index 25928d87..328883c8 100644
--- a/nonebot/adapters/_base.py
+++ b/nonebot/adapters/_base.py
@@ -351,7 +351,7 @@ class Event(abc.ABC, BaseModel):
         json_encoders = {Message: DataclassEncoder}
 
     @abc.abstractmethod
-    def get_type(self) -> Literal["message", "notice", "request", "meta_event"]:
+    def get_type(self) -> str:
         """
         :说明:
 
@@ -360,6 +360,7 @@ class Event(abc.ABC, BaseModel):
         :返回:
 
           * ``Literal["message", "notice", "request", "meta_event"]``
+          * ``str``
         """
         raise NotImplementedError
 
diff --git a/packages/nonebot-adapter-cqhttp/nonebot/adapters/cqhttp/event.py b/packages/nonebot-adapter-cqhttp/nonebot/adapters/cqhttp/event.py
index 2037577b..53497870 100644
--- a/packages/nonebot-adapter-cqhttp/nonebot/adapters/cqhttp/event.py
+++ b/packages/nonebot-adapter-cqhttp/nonebot/adapters/cqhttp/event.py
@@ -25,10 +25,10 @@ class Event(BaseEvent):
     __event__ = ""
     time: int
     self_id: int
-    post_type: Literal["message", "notice", "request", "meta_event"]
+    post_type: str
 
     @overrides(BaseEvent)
-    def get_type(self) -> Literal["message", "notice", "request", "meta_event"]:
+    def get_type(self) -> str:
         return self.post_type
 
     @overrides(BaseEvent)