A semiconductor device includes: a semiconductor substrate; a lateral MOSFET formed in an upper portion of a first region of the semiconductor substrate; a vertical MOSFET formed in a second region of the semiconductor substrate; a backside electrode formed on a lower surface of the semiconductor substrate and connected to a lower region of source/drain regions of the vertical MOSFET; and a connecting member penetrating the semiconductor substrate and connecting one of source/drain regions of the lateral MOSFET to the backside electrode.