Provided is a mounting structure including an electronic control unit, a plurality of support brackets, a transaxle case, an intermediate bracket protruding from the transaxle case toward a rear side of the vehicle, and an engaging projection. The engaging projection is a projection that is provided to at least one of an upper surface of the intermediate bracket or a bottom surface of the electronic control unit in a region where the intermediate bracket is in surface contact with a mounting surface of the transaxle case, the engaging projection protruding in a direction toward the upper surface of the intermediate bracket and the bottom surface of the electronic control unit. The engaging projection presses the intermediate bracket against the mounting surface of the transaxle case responding to displacement of the electronic control unit at the time of vehicle collision.