diff --git a/gitk b/gitk
index 3520bdaebc29fd6c93724b0a46484ee5e9403831..bfc5cfabd312ff6efe43bb84fe9e8d0f0d970ab1 100755
--- a/gitk
+++ b/gitk
@@ -445,7 +445,7 @@ proc stop_instance {inst} {
 	set pid [pid $fd]
 
 	if {$::tcl_platform(platform) eq {windows}} {
-	    exec kill -f $pid
+	    exec taskkill /pid $pid
 	} else {
 	    exec kill $pid
 	}