diff --git a/lcl/interfaces/qt/qtwinapi.inc b/lcl/interfaces/qt/qtwinapi.inc
index 5c805c349a..206bb16747 100644
--- a/lcl/interfaces/qt/qtwinapi.inc
+++ b/lcl/interfaces/qt/qtwinapi.inc
@@ -5077,6 +5077,23 @@ begin
   end;
 end;
 
+function TQtWidgetSet.PaintRgn(DC: HDC; RGN: HRGN): Boolean;
+var
+  APath: QPainterPathH;
+begin
+  Result := False;
+  if not IsValidDC(DC) or not IsValidGDIObject(RGN) then
+    exit;
+  if TQtRegion(RGN).FHandle = nil then
+    exit;
+  APath := QPainterPath_create;
+  QPainterPath_addRegion(APath, TQtRegion(RGN).FHandle);
+  QPainterPath_closeSubpath(APath);
+  QPainter_fillPath(TQtDeviceContext(DC).Widget, APath, QPainter_brush(TQtDeviceContext(DC).Widget));
+  QPainterPath_destroy(APath);
+  Result := True;
+end;
+
 function TQtWidgetSet.PeekMessage(var lpMsg : TMsg; Handle : HWND; wMsgFilterMin, wMsgFilterMax,wRemoveMsg : UINT): Boolean;
 begin
   Result := False;
diff --git a/lcl/interfaces/qt/qtwinapih.inc b/lcl/interfaces/qt/qtwinapih.inc
index da59d20a58..533940d426 100644
--- a/lcl/interfaces/qt/qtwinapih.inc
+++ b/lcl/interfaces/qt/qtwinapih.inc
@@ -158,6 +158,7 @@ function MoveToEx(DC: HDC; X, Y: Integer; OldPoint: PPoint): Boolean; override;
 
 function OffsetRgn(RGN: HRGN; nXOffset, nYOffset: Integer): Integer; override;
 
+function PaintRgn(DC: HDC; RGN: HRGN): Boolean; override;
 function PeekMessage(var lpMsg : TMsg; Handle : HWND; wMsgFilterMin, wMsgFilterMax,wRemoveMsg : UINT): Boolean; override;
 function PolyBezier(DC: HDC; Points: PPoint; NumPts: Integer; Filled, Continuous: boolean): boolean; override;
 function Polygon(DC: HDC; Points: PPoint; NumPts: Integer; Winding: boolean): boolean; override;