diff --git a/pkgs/by-name/ms/mscgen/package.nix b/pkgs/by-name/ms/mscgen/package.nix
index d5f58b968ecd..b341ea5b826f 100644
--- a/pkgs/by-name/ms/mscgen/package.nix
+++ b/pkgs/by-name/ms/mscgen/package.nix
@@ -18,7 +18,7 @@ stdenv.mkDerivation (finalAttrs: {
   version = "0.20";
 
   src = fetchurl {
-    url = "http://www.mcternan.me.uk/mscgen/software/mscgen-src-${finalAttrs.version}.tar.gz";
+    url = "https://www.mcternan.me.uk/mscgen/software/mscgen-src-${finalAttrs.version}.tar.gz";
     sha256 = "3c3481ae0599e1c2d30b7ed54ab45249127533ab2f20e768a0ae58d8551ddc23";
   };