diff --git a/tox.ini b/tox.ini
index 1bb3f22c..7ab988ac 100644
--- a/tox.ini
+++ b/tox.ini
@@ -33,7 +33,8 @@ deps=
     matplotlib
     numpy
     pandas
-    keras: keras
+    py27-keras: keras<2.5
+    !py27-keras: keras
     py3{6,7,8,9}: rich
     tf: tensorflow!=2.5.0
 commands=