The reliability of the terminal connection portions excellent in liquid-tightness to provide a high compact power converter. Power conversion device according to the present invention includes a case for accommodating the power semiconductor, a flow path formation member forming a flow path between the outer surface of the case, a first fixing member in contact with the coolant flowing through the flow path the first contact with the fixing member and the channel member, and a second fixing member which covers the displacement direction by water pressure of the case of the first fixing member.