diff --git a/pkgs/development/libraries/gtk+/3.x.nix b/pkgs/development/libraries/gtk+/3.x.nix
index a2da4c7b033..a8b0118567a 100644
--- a/pkgs/development/libraries/gtk+/3.x.nix
+++ b/pkgs/development/libraries/gtk+/3.x.nix
@@ -11,8 +11,8 @@ assert cupsSupport -> cups != null;
 with stdenv.lib;
 
 let
-  ver_maj = "3.18";
-  ver_min = "5";
+  ver_maj = "3.20";
+  ver_min = "0";
   version = "${ver_maj}.${ver_min}";
 in
 stdenv.mkDerivation rec {
@@ -20,7 +20,7 @@ stdenv.mkDerivation rec {
 
   src = fetchurl {
     url = "mirror://gnome/sources/gtk+/${ver_maj}/gtk+-${version}.tar.xz";
-    sha256 = "107aeb9a4244ce3c044becdd6dffc32d83202595181597180d4c736302a71852";
+    sha256 = "00yqlqxzhpizdbg71g3gqlgch9gsp36ln1ybdiiwi7lmdr53lg8w";
   };
 
   outputs = [ "dev" "out" ];