The invention provides a power conversion device capable of cooling the power semiconductors efficiently and downsizing the device. The power conversion device comprises a plurality of power semiconductor devices, a heat receiving member, a plurality of heat pipes and a plurality of heat radiating fins, wherein the plurality of semiconductor devices are attached to one side of the heat receiving member, and the plurality of heat pipes are attached to the other side of the heat receiving member, the plurality of heat pipes have heat receiving sections thermally connected to the heat receiving member, and a portion of the plurality of heat pipes has heat radiating sections erected from both ends of the heat receiving section, and another portion of the plurality of heat pipes has a heat radiating section erected from only one side of the heat receiving section, the plurality of heat radiating fins are disposed on the heat radiating sections of the plurality of heat pipes, and the pipes composing the heat radiating sections of the heat pipes are arranged in a zigzag manner.