There is provided a technology for realizing a low-cost electric power converter operating at low noise under a high-temperature environment. The electric power converter is provided with an enclosure, a power module including a switching element, a driver circuit for generating a signal for driving the switching element, a control circuit board for generating an actuating signal to be sent out to the driver circuit, a base plate with the control circuit board mounted thereon, and a connection part for connecting between the enclosure and the control circuit board. The enclosure is provided with two openings adjacent to each other, and the base plate or the opening of the enclosure is provided with the connection part.