--- xdg-su~
+++ xdg-su
@@ -505,6 +505,8 @@ su_kde()
 {
     if [ x"$KDE_SESSION_VERSION" = x"4" ]; then
         KDESU=`kde4-config --locate kdesu --path exe 2>/dev/null`
+    elif [ x"$KDE_SESSION_VERSION" = x"5" ]; then
+        KDESU=/usr/libexec/kf5/kdesu
     else
         KDESU=`which kdesu 2>/dev/null`
     fi