diff --git a/pkgs/development/libraries/opencascade/6.5.nix b/pkgs/development/libraries/opencascade/6.5.nix
index a150f53bb860..b0ef9e83242a 100644
--- a/pkgs/development/libraries/opencascade/6.5.nix
+++ b/pkgs/development/libraries/opencascade/6.5.nix
@@ -2,10 +2,10 @@
 ftgl, freetype}:
 
 stdenv.mkDerivation rec {
-  name = "opencascade-6.5.4";
+  name = "opencascade-6.5.5";
   src = fetchurl {
-    url = http://files.opencascade.com/OCCT/OCC_6.5.4_release/OpenCASCADE654.tar.gz;
-    sha256 = "1di08mc0wly4cdi3rh9kj52bk0bfpyk6dy03c9yfnv04i7z03kmy";
+    url = http://files.opencascade.com/OCCT/OCC_6.5.5_release/OpenCASCADE655.tgz;
+    sha256 = "1dnik00adfh6dxvn9kgf35yjda8chbi05f71i9119idmmrcapipm";
   };
 
   buildInputs = [ mesa tcl tk file libXmu automake autoconf libtool qt4 ftgl freetype ];