diff --git a/src/gui/image/qimage.cpp b/src/gui/image/qimage.cpp
index ef0481bdb2f..7b3ca0f7ee1 100644
--- a/src/gui/image/qimage.cpp
+++ b/src/gui/image/qimage.cpp
@@ -2627,12 +2627,9 @@ void QImage::setPixelColor(int x, int y, const QColor &color)
         ((uint *)s)[x] = qConvertRgb64ToRgb30<PixelOrderRGB>(c);
         return;
     case Format_RGBX64:
-        ((QRgba64 *)s)[x] = color.rgba64();
-        ((QRgba64 *)s)[x].setAlpha(65535);
-        return;
     case Format_RGBA64:
     case Format_RGBA64_Premultiplied:
-        ((QRgba64 *)s)[x] = color.rgba64();
+        ((QRgba64 *)s)[x] = c;
         return;
     default:
         setPixel(x, y, c.toArgb32());
diff --git a/tests/auto/gui/image/qimage/tst_qimage.cpp b/tests/auto/gui/image/qimage/tst_qimage.cpp
index bb81b9f61fe..b2873d6f8a7 100644
--- a/tests/auto/gui/image/qimage/tst_qimage.cpp
+++ b/tests/auto/gui/image/qimage/tst_qimage.cpp
@@ -3324,6 +3324,14 @@ void tst_QImage::pixelColor()
     // Try setting an invalid color.
     QTest::ignoreMessage(QtWarningMsg, "QImage::setPixelColor: color is invalid");
     argb32.setPixelColor(0, 0, QColor());
+
+    // Test correct premultiplied handling of RGBA64 as well
+    QImage rgba64(1, 1, QImage::Format_RGBA64);
+    QImage rgba64pm(1, 1, QImage::Format_RGBA64_Premultiplied);
+    rgba64.setPixelColor(QPoint(0, 0), c);
+    rgba64pm.setPixelColor(QPoint(0, 0), c);
+    QCOMPARE(rgba64.pixelColor(QPoint(0, 0)), c);
+    QCOMPARE(rgba64pm.pixelColor(QPoint(0, 0)), c);
 }
 
 void tst_QImage::pixel()