diff --git a/CHANGES/3720.bugfix b/CHANGES/3720.bugfix
new file mode 100644
index 00000000000..f02318f417e
--- /dev/null
+++ b/CHANGES/3720.bugfix
@@ -0,0 +1 @@
+Fixed return type annotation for WSMessage.json()
diff --git a/CONTRIBUTORS.txt b/CONTRIBUTORS.txt
index e4b86241333..e04e846f397 100644
--- a/CONTRIBUTORS.txt
+++ b/CONTRIBUTORS.txt
@@ -200,6 +200,7 @@ Simon Kennedy
 Sin-Woo Bang
 Stanislas Plum
 Stanislav Prokop
+Stepan Pletnev
 Stephen Granade
 Steven Seguin
 Sunghyun Hwang
diff --git a/aiohttp/http_websocket.py b/aiohttp/http_websocket.py
index d8fc10f4567..f27c547f49d 100644
--- a/aiohttp/http_websocket.py
+++ b/aiohttp/http_websocket.py
@@ -83,7 +83,7 @@ class WSMsgType(IntEnum):
 class WSMessage(_WSMessageBase):
 
     def json(self, *,  # type: ignore
-             loads: Callable[[Any], Any]=json.loads) -> None:
+             loads: Callable[[Any], Any]=json.loads) -> Any:
         """Return parsed JSON data.
 
         .. versionadded:: 0.22