diff --git a/CHANGES/4057.bugfix b/CHANGES/4057.bugfix
new file mode 100644
index 00000000000..990694930eb
--- /dev/null
+++ b/CHANGES/4057.bugfix
@@ -0,0 +1 @@
+Update multidict requirement to >= 4.5
diff --git a/setup.py b/setup.py
index 3cd894f360c..ac6457af823 100644
--- a/setup.py
+++ b/setup.py
@@ -71,7 +71,7 @@ def build_extension(self, ext):
 install_requires = [
     'attrs>=17.3.0',
     'chardet>=2.0,<4.0',
-    'multidict>=4.0,<5.0',
+    'multidict>=4.5,<5.0',
     'async_timeout>=3.0,<4.0',
     'yarl>=1.0,<2.0',
     'idna-ssl>=1.0; python_version<"3.7"',