diff --git a/moffy-samples-gtk3-run.cabal b/moffy-samples-gtk3-run.cabal
--- a/moffy-samples-gtk3-run.cabal
+++ b/moffy-samples-gtk3-run.cabal
@@ -5,7 +5,7 @@
 -- see: https://github.com/sol/hpack
 
 name:           moffy-samples-gtk3-run
-version:        0.1.0.3
+version:        0.1.0.4
 synopsis:       Package to run moffy samples - GTK3 version
 description:    Please see the README on GitHub at <https://github.com/YoshikuniJujo/moffy-samples-gtk3-run#readme>
 category:       Control
diff --git a/src/Control/Moffy/Samples/Run/Gtk3.hs b/src/Control/Moffy/Samples/Run/Gtk3.hs
--- a/src/Control/Moffy/Samples/Run/Gtk3.hs
+++ b/src/Control/Moffy/Samples/Run/Gtk3.hs
@@ -128,7 +128,8 @@
 
 	forkIO . forever $ atomically (readTChan cv) >>= \case
 		Stopped -> void $ G.idleAdd
-			(\_ -> Gtk.mainQuit >> pure False) Null
+			(\_ -> Gtk.Window.close w >> Gtk.mainQuit >> pure False)
+			Null
 		View v -> do
 			atomically $ writeTVar crd v
 			void $ G.idleAdd
diff --git a/src/Stopgap/Graphics/UI/Gtk/Window.hsc b/src/Stopgap/Graphics/UI/Gtk/Window.hsc
--- a/src/Stopgap/Graphics/UI/Gtk/Window.hsc
+++ b/src/Stopgap/Graphics/UI/Gtk/Window.hsc
@@ -33,3 +33,8 @@
 new = c_gtk_window_new
 
 foreign import ccall "gtk_window_new" c_gtk_window_new :: Type -> IO W
+
+close :: W -> IO ()
+close = c_gtk_window_close
+
+foreign import ccall "gtk_window_close" c_gtk_window_close :: W -> IO ()