Abstract: A power semiconductor module, having a metal base plate for mounting on a heat sink. The module comprises a framelike housing, a cover, terminal elements, leading to the outside of the housing, for load contacts and auxiliary contacts, and having at least one electrically insulating substrate, disposed inside the housing. The substrate includes an insulating body and a plurality of metal connecting tracks, electrically insulated from one another. Power semiconductor components are located on the connecting tracks and connected to these connecting tracks via appropriate circuitry. The base plate has a stiffening structure, which extends near and along a side of the base plate, and in the longitudinal direction of the base plate. The stiffening structure is formed of the base plate material itself by deformation and protrudes out of the upper surface of the base plate.