An electric power converter includes a laminated body, a capacitor, a case, and a pressing member. The laminated body is formed by laminating semiconductor modules and cooling pipes. The pressing member presses the laminated body in a laminating direction of the laminated body. The case has outer wall portions that form an outer shell, and partition wall portions formed in the case and are connected to the outer wall portions. The capacitor has capacitor elements and a sealing member. The sealing member is filled in a capacitor housing space in a state where the capacitor elements are sealed. Pressing force of the pressing member is applied to an interposing partition wall portion interposing between the laminated body and the capacitor among the partition wall portions. A thickness of the interposing partition wall portion is made thinner than any other parts of the outer wall portions.