The invention relates to a molding milling cutter comprising a cutter body and a first cutting edge and a second cutting edge which are formed on the cutter body, wherein the first cutting edge and the second cutting edge are staggered in the rotating direction of the cutter body. A cutting face formed when the first cutting edge rotates a circle around the rotating axis of the cutter body insects with the second cutting edge. The invention also provides a method for processing by utilizing the molding milling cutter. The molding milling cutter and the molding method can form two surfaces thejoint of which is sharp-angled by one-time processing only. The invention has the advantages of higher processing efficiency and lower cost and is easy to ensure the processing precision.