diff --git a/stdlib/weakref.pyi b/stdlib/weakref.pyi
index e81052de7d26..1364a6177d1d 100644
--- a/stdlib/weakref.pyi
+++ b/stdlib/weakref.pyi
@@ -54,7 +54,8 @@ class ProxyType(Generic[_T]):  # "weakproxy"
 
 @disjoint_base
 class ReferenceType(Generic[_T]):  # "weakref"
-    __callback__: Callable[[Self], Any]
+    @property
+    def __callback__(self) -> Callable[[Self], Any] | None: ...
     def __new__(cls, o: _T, callback: Callable[[Self], Any] | None = ..., /) -> Self: ...
     def __call__(self) -> _T | None: ...
     def __eq__(self, value: object, /) -> bool: ...