diff --git a/pkgs/development/libraries/fltk/default.nix b/pkgs/development/libraries/fltk/default.nix
index 5cbd993fc646..6045fd6bf21e 100644
--- a/pkgs/development/libraries/fltk/default.nix
+++ b/pkgs/development/libraries/fltk/default.nix
@@ -4,7 +4,7 @@
 }:
 
 let
-  version = "1.3.5";
+  version = "1.3.6";
 in
 
 stdenv.mkDerivation {
@@ -13,7 +13,7 @@ stdenv.mkDerivation {
 
   src = fetchurl {
     url = "https://www.fltk.org/pub/fltk/${version}/fltk-${version}-source.tar.gz";
-    sha256 = "00jp24z1818k9n6nn6lx7qflqf2k13g4kxr0p8v1d37kanhb4ac7";
+    sha256 = "1arp1niiz3qxm8iacpmilwpc5rinsm6hsk4a6fsxfywvkvppbb4s";
   };
 
   patches = lib.optionals stdenv.isDarwin [ ./nsosv.patch ];