Abstract: The metallic case of a power conversion apparatus includes a casing having a side wall, as well as an upper case and a lower case, a first area being formed between a cooling jacket provided at the inner periphery of the side wall and the lower case, the metal base plate dividing the first area between the cooling jacket and the upper case into a lower side second area and an upper side third area, first and second power modules being fastened to a top surface and a capacitor module being provided in the first area, driving circuits that drive inverter circuits of the power modules respectively being provided in the second area, and a control circuit that controls the driver circuits being provided in the third area.