diff --git a/python/httpx/_httpx/__init__.pyi b/python/httpx/_httpx/__init__.pyi
index 1f2082a0..bae19238 100644
--- a/python/httpx/_httpx/__init__.pyi
+++ b/python/httpx/_httpx/__init__.pyi
@@ -13,7 +13,7 @@ QueryParamTypes = typing.Union[
 
 @typing.final
 class QueryParams(typing.Mapping[str, str]):
-    def __init__(self, *args: QueryParamTypes | None, **kwargs: typing.Any) -> None:...
+    def __new__(cls, *args: QueryParamTypes | None, **kwargs: typing.Any) -> None:...
     def keys(self) -> typing.KeysView[str]:
         """
         Return all the keys in the query params.