diff --git a/src/widgets/kernel/qlayout.cpp b/src/widgets/kernel/qlayout.cpp
index 46cab90ab4..f124f1ed8e 100644
--- a/src/widgets/kernel/qlayout.cpp
+++ b/src/widgets/kernel/qlayout.cpp
@@ -576,11 +576,12 @@ void QLayoutPrivate::doResize(const QSize &r)
     int mbh = menuBarHeightForWidth(menubar, r.width());
     QWidget *mw = q->parentWidget();
     QRect rect = mw->testAttribute(Qt::WA_LayoutOnEntireRect) ? mw->rect() : mw->contentsRect();
+    const int mbTop = rect.top();
     rect.setTop(rect.top() + mbh);
     q->setGeometry(rect);
 #ifndef QT_NO_MENUBAR
     if (menubar)
-        menubar->setGeometry(0,0,r.width(), mbh);
+        menubar->setGeometry(rect.left(), mbTop, r.width(), mbh);
 #endif
 }
 
diff --git a/tests/auto/widgets/widgets/qmainwindow/tst_qmainwindow.cpp b/tests/auto/widgets/widgets/qmainwindow/tst_qmainwindow.cpp
index f2ce2d1d96..15f2f88a8d 100644
--- a/tests/auto/widgets/widgets/qmainwindow/tst_qmainwindow.cpp
+++ b/tests/auto/widgets/widgets/qmainwindow/tst_qmainwindow.cpp
@@ -780,6 +780,9 @@ void tst_QMainWindow::contentsMargins()
     mw.show();
     QVERIFY(QTest::qWaitForWindowExposed(&mw));
 
+    QCOMPARE(mw.menuBar()->geometry().left(), contentsMargin);
+    QCOMPARE(mw.menuBar()->geometry().top(), contentsMargin);
+
     QCOMPARE(mw.statusBar()->geometry().left(), contentsMargin);
     QCOMPARE(mw.statusBar()->geometry().bottom() + 1, mw.height() - contentsMargin);
 }