diff --git a/src/platform/qt/GBAApp.cpp b/src/platform/qt/GBAApp.cpp
index 2a4849c49..20c19c027 100644
--- a/src/platform/qt/GBAApp.cpp
+++ b/src/platform/qt/GBAApp.cpp
@@ -118,6 +118,9 @@ Window* GBAApp::newWindow() {
 	int windowId = m_multiplayer.attached();
 	connect(w, &Window::destroyed, [this, w]() {
 		m_windows.removeAll(w);
+		for (Window* w : m_windows) {
+			w->updateMultiplayerStatus(m_windows.count() < MAX_GBAS);
+		}
 	});
 	m_windows.append(w);
 	w->setAttribute(Qt::WA_DeleteOnClose);
@@ -125,6 +128,9 @@ Window* GBAApp::newWindow() {
 	w->show();
 	w->controller()->setMultiplayerController(&m_multiplayer);
 	w->multiplayerChanged();
+	for (Window* w : m_windows) {
+		w->updateMultiplayerStatus(m_windows.count() < MAX_GBAS);
+	}
 	return w;
 }
 
diff --git a/src/platform/qt/Window.cpp b/src/platform/qt/Window.cpp
index 755805087..c34f40c4a 100644
--- a/src/platform/qt/Window.cpp
+++ b/src/platform/qt/Window.cpp
@@ -1024,11 +1024,11 @@ void Window::setupMenu(QMenuBar* menubar) {
 #endif
 
 	fileMenu->addSeparator();
-	QAction* multiWindow = new QAction(tr("New multiplayer window"), fileMenu);
-	connect(multiWindow, &QAction::triggered, [this]() {
+	m_multiWindow = new QAction(tr("New multiplayer window"), fileMenu);
+	connect(m_multiWindow, &QAction::triggered, [this]() {
 		GBAApp::app()->newWindow();
 	});
-	addControlledAction(fileMenu, multiWindow, "multiWindow");
+	addControlledAction(fileMenu, m_multiWindow, "multiWindow");
 
 #ifndef Q_OS_MAC
 	fileMenu->addSeparator();
diff --git a/src/platform/qt/Window.h b/src/platform/qt/Window.h
index a2e6ca23d..756293615 100644
--- a/src/platform/qt/Window.h
+++ b/src/platform/qt/Window.h
@@ -50,6 +50,8 @@ public:
 
 	void resizeFrame(const QSize& size);
 
+	void updateMultiplayerStatus(bool canOpenAnother) { m_multiWindow->setEnabled(canOpenAnother); }
+
 signals:
 	void startDrawing(mCoreThread*);
 	void shutdown();
@@ -160,6 +162,7 @@ private:
 #ifdef M_CORE_GBA
 	QList<QAction*> m_gbaActions;
 #endif
+	QAction* m_multiWindow;
 	QMap<int, QAction*> m_frameSizes;
 	LogController m_log;
 	LogView* m_logView;