diff --git a/pkgs/development/tools/analysis/checkstyle/default.nix b/pkgs/development/tools/analysis/checkstyle/default.nix
index 4d47d5134371..f757d0e96199 100644
--- a/pkgs/development/tools/analysis/checkstyle/default.nix
+++ b/pkgs/development/tools/analysis/checkstyle/default.nix
@@ -1,12 +1,12 @@
 { stdenv, fetchurl }:
 
 stdenv.mkDerivation rec {
-  version = "6.5";
+  version = "6.6";
   name = "checkstyle-${version}";
 
   src = fetchurl {
     url = "mirror://sourceforge/checkstyle/${version}/${name}-bin.tar.gz";
-    sha256 = "1231rzmk7kzv77hpa0jj227152br9ahjdvxvzifk0mdfw0b34rdl";
+    sha256 = "1pniql23f8fsr7yhcxvrc65rdynrwpwl6vxl2jdsj4a37br8mr0d";
   };
 
   installPhase = ''