diff --git a/setup.py b/setup.py
index 2bf9202..64cdb1d 100644
--- a/setup.py
+++ b/setup.py
@@ -28,7 +28,7 @@ setup(
     license='Apache-2.0',
     install_requires=[
         'absl-py~=1.0.0',
-        'attrs~=21.2.0',
+        'attrs~=21.4.0',
         'dm-tree~=0.1.1',
         'matplotlib~=3.3.4',
         'numpy~=1.21.5',