diff --git a/pkgs/development/tools/parsing/bison/3.x.nix b/pkgs/development/tools/parsing/bison/3.x.nix
index d75a7e0ee3db..bae134ea3a51 100644
--- a/pkgs/development/tools/parsing/bison/3.x.nix
+++ b/pkgs/development/tools/parsing/bison/3.x.nix
@@ -1,11 +1,11 @@
 { stdenv, fetchurl, m4, perl, help2man }:
 
 stdenv.mkDerivation rec {
-  name = "bison-3.1";
+  name = "bison-3.2.1";
 
   src = fetchurl {
     url = "mirror://gnu/bison/${name}.tar.gz";
-    sha256 = "0ip9krjf0lw57pk3wfbxgjhif1i18hm3vh35d1ifrvhnafskdjx7";
+    sha256 = "1pgcvwzzlckb83sdcljz75hg71zwbc2a4pl5ycwxsxw05423gwq1";
   };
 
   patches = []; # remove on another rebuild