diff --git a/pkgs/desktops/xfce/core/xfce4-light-locker.patch b/pkgs/desktops/xfce/core/xfce4-light-locker.patch
new file mode 100644
index 000000000000..4e1dcc1efa71
--- /dev/null
+++ b/pkgs/desktops/xfce/core/xfce4-light-locker.patch
@@ -0,0 +1,16 @@
+--- ./scripts/xflock4.orig	2017-08-06 23:05:53.807688995 +0100
++++ ./scripts/xflock4	2017-08-06 23:09:06.171789989 +0100
+@@ -24,10 +24,11 @@
+ PATH=/bin:/usr/bin
+ export PATH
+
+-# Lock by xscreensaver or gnome-screensaver, if a respective daemon is running
++# Lock by xscreensaver, gnome-screensaver or light-locker, if a respective daemon is running
+ for lock_cmd in \
+     "xscreensaver-command -lock" \
+-    "gnome-screensaver-command --lock"
++    "gnome-screensaver-command --lock" \
++    "light-locker-command -l"
+ do
+     $lock_cmd >/dev/null 2>&1 && exit
+ done
diff --git a/pkgs/desktops/xfce/core/xfce4-session.nix b/pkgs/desktops/xfce/core/xfce4-session.nix
index a0568b0dd395..edc810d38972 100644
--- a/pkgs/desktops/xfce/core/xfce4-session.nix
+++ b/pkgs/desktops/xfce/core/xfce4-session.nix
@@ -16,6 +16,11 @@ stdenv.mkDerivation rec {
     sha256 = "97d7f2a2d0af7f3623b68d1f04091e02913b28f9555dab8b0d26c8a1299d08fd";
   };
 
+  patches = [
+    # Fix "lock screen" not working for light-locker
+    ./xfce4-light-locker.patch
+  ];
+
   buildInputs =
     [ pkgconfig intltool gtk libxfce4util libxfce4ui libwnck dbus_glib
       xfconf xfce4panel libglade xorg.iceauth xorg.libSM