Disclosed are a power conversion device and a photovoltaic module including the same. The power conversion device includes a full-bridge switching unit including first to fourth switching elements, a first transformer having an input terminal connected between the first switching element and the second switching element in the full-bridge switching unit and an output terminal connected between the third switching element and the fourth switching element in the full-bridge switching unit, wherein the first switching element is serially connected to the second switching element, and the third switching element is serially connected to the fourth switching element, and a second transformer connected to the full-bridge switching unit as a half-bridge, wherein the full-bridge switching unit coverts a first DC power input to the first transformer into a first alternating current AC waveform, based on variable duty switching.