To provide a technology of protecting an insulating plate sandwiched between a semiconductor card and a cooling plate from breakage in a semiconductor module in which the semiconductor cards and the cooling plates are alternately laminated and attached firmly by energization on the laminate in a lamination direction.

A semiconductor module 100 is formed by a plurality of tabular cooling plates 2 and a plurality of tabular semiconductor cards 3 each housing a semiconductor element, which are alternately laminated one by one. The semiconductor module 100 includes insulating plates 4 each insulating the semiconductor card 3 from the cooling plate 2 and sandwiched between the cooling plate and the semiconductor card. The laminate is energized by a plate spring 14 in a lamination direction to continuously and firmly attach the cooling plates 2, the insulating plates 4 and the semiconductor cards 3. In the semiconductor module 100, dents 2a are provided on a cooling plate surface opposed to the insulating plate 4, and the dents 2a are arranged such that at least a part of an edge of each dent 2a is positioned inside an edge of the semiconductor card 3.