diff --git a/src/printsupport/kernel/qprinter.cpp b/src/printsupport/kernel/qprinter.cpp
index 437a68e609..8ed2732c1e 100644
--- a/src/printsupport/kernel/qprinter.cpp
+++ b/src/printsupport/kernel/qprinter.cpp
@@ -1224,7 +1224,10 @@ void QPrinter::setPageSize(PageSize newPageSize)
 
 void QPrinter::setPaperSize(const QSizeF &paperSize, QPrinter::Unit unit)
 {
-    setPageSize(QPageSize(paperSize, QPageSize::Unit(unit)));
+    if (unit == QPrinter::DevicePixel)
+        setPageSize(QPageSize(paperSize * qt_pixelMultiplier(resolution()), QPageSize::Point));
+    else
+        setPageSize(QPageSize(paperSize, QPageSize::Unit(unit)));
 }
 
 /*!
diff --git a/tests/auto/printsupport/kernel/qprinter/tst_qprinter.cpp b/tests/auto/printsupport/kernel/qprinter/tst_qprinter.cpp
index 78aa0af43d..62bd9828ba 100644
--- a/tests/auto/printsupport/kernel/qprinter/tst_qprinter.cpp
+++ b/tests/auto/printsupport/kernel/qprinter/tst_qprinter.cpp
@@ -526,7 +526,7 @@ void tst_QPrinter::testCustomPageSizes()
 {
     QPrinter p;
 
-    QSizeF customSize(8.5, 11.0);
+    QSizeF customSize(7.0, 11.0);
     p.setPaperSize(customSize, QPrinter::Inch);
 
     QSizeF paperSize = p.paperSize(QPrinter::Inch);
@@ -538,6 +538,16 @@ void tst_QPrinter::testCustomPageSizes()
     paperSize = p.paperSize(QPrinter::Inch);
     QCOMPARE(paperSize.width(), customSize.width());
     QCOMPARE(paperSize.height(), customSize.height());
+
+    const QSizeF sizeInPixels = p.paperSize(QPrinter::DevicePixel);
+    QPrinter p3;
+    p3.setPaperSize(sizeInPixels, QPrinter::DevicePixel);
+    paperSize = p3.paperSize(QPrinter::Inch);
+    QCOMPARE(paperSize.width(), customSize.width());
+    QCOMPARE(paperSize.height(), customSize.height());
+    QPageSize pageSize = p3.pageLayout().pageSize();
+    QCOMPARE(pageSize.key(), QString("Custom.504x792"));
+    QCOMPARE(pageSize.name(), QString("Custom (504pt x 792pt)"));
 }
 
 void tst_QPrinter::customPaperSizeAndMargins_data()