diff --git a/playwright/_impl/_js_handle.py b/playwright/_impl/_js_handle.py
index ce11aaa05..051967282 100644
--- a/playwright/_impl/_js_handle.py
+++ b/playwright/_impl/_js_handle.py
@@ -98,7 +98,7 @@ def serialize_value(value: Any, handles: List[JSHandle], depth: int) -> Any:
     if depth > 100:
         raise Error("Maximum argument depth exceeded")
     if value is None:
-        return dict(v="undefined")
+        return dict(v="null")
     if isinstance(value, float):
         if value == float("inf"):
             return dict(v="Infinity")
diff --git a/tests/async/test_evaluate.py b/tests/async/test_evaluate.py
index 3505a75fc..8134306e3 100644
--- a/tests/async/test_evaluate.py
+++ b/tests/async/test_evaluate.py
@@ -142,7 +142,7 @@ async def test_evaluate_return_complex_objects(page):
 
 async def test_evaluate_accept_none_as_one_of_multiple_parameters(page):
     result = await page.evaluate(
-        '({ a, b }) => Object.is(a, undefined) && Object.is(b, "foo")',
+        '({ a, b }) => Object.is(a, null) && Object.is(b, "foo")',
         {"a": None, "b": "foo"},
     )
     assert result