A power conversion device includes a cooler, a terminal block and a case. The cooler defines an internal space through which a refrigerant flows. The terminal block covers a conducive part. The case accommodates the cooler and the terminal block therein. The case has an opening on its lateral wall portion for allowing connection between the conductive part of the terminal block inside the case and an external load disposed outside the case. At least a part of the terminal block is located closer to the opening than the cooler in a first direction to which an inner surface and an outer surface of the lateral wall portion of the case defining the opening are opposed, and is located between the cooler and an upper end of the opening in a second direction orthogonal to the first direction.