A power semiconductor module system includes a power semiconductor module, a heat sink and at least one fastener. The power semiconductor module includes a bottom side with a first thermal contact surface and the heat sink includes a top side with a second thermal contact surface. The power semiconductor module is conjoined with the heat sink by means of the at least one fastener. The power semiconductor module includes a number N1≧1 of first positioning elements and the heat sink a number N2≧1 of second positioning elements. Each of the first positioning elements corresponds to one of the second positioning elements and forms a pair therewith. The power semiconductor module and the heat sink are alignable relative to one another so that the two positioning elements of each of the pairs are interfitted when the power semiconductor module is mounted on the heat sink.