An object is to obtain long-term reliability of an electric connection in a power semiconductor module. In a power semiconductor module, the main circuit interconnection directly connected to a power semiconductor chip (3) is formed of a busbar (6) and the power semiconductor chip (3) and the busbar electrode (6a) of the busbar (6) are electrically connected through a conductive resin (12). A member (13) having lower thermal expansion than the busbar electrode (6a) is joined to the busbar electrode (6a) in the part adjacent to said power semiconductor chip (3).