diff --git a/setup.py b/setup.py
index 6bee91e5616c..37cb98e1070a 100644
--- a/setup.py
+++ b/setup.py
@@ -178,7 +178,7 @@ def run(self):
       classifiers=classifiers,
       cmdclass=cmdclass,
       # When changing this, also update test-requirements.txt.
-      install_requires=['typed-ast >= 1.3.5, < 1.4.0',
+      install_requires=['typed_ast >= 1.4.0, < 1.5.0',
                         'mypy_extensions >= 0.4.0, < 0.5.0',
                         ],
       # Same here.
diff --git a/test-requirements.txt b/test-requirements.txt
index 605d64c6562f..6ce7e3856bb1 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -8,7 +8,7 @@ psutil>=4.0
 pytest>=4.4
 pytest-xdist>=1.22
 pytest-cov>=2.4.0
-typed-ast>=1.3.5,<1.4.0
+typed_ast>=1.4.0,<1.5.0
 typing>=3.5.2; python_version < '3.5'
 py>=1.5.2
 virtualenv