diff --git a/utils/casctl b/utils/casctl
index f811596..2171e70 100755
--- a/utils/casctl
+++ b/utils/casctl
@@ -10,8 +10,8 @@ import sys
 
 import opencas
 
-if sys.version_info < (3, 5):
-    raise RuntimeError('At least Python 3.5 is required')
+if sys.version_info < (3, 6):
+    raise RuntimeError('At least Python 3.6 is required')
 
 def eprint(*args, **kwargs):
     print(*args, file=sys.stderr, **kwargs)