A semiconductor device has a semiconductor chip, a signal lead that is arranged in a periphery of the semiconductor chip and has a main surface and a rear surface opposed to the main surface, a wire that electrically connects the semiconductor chip and the main surface of the signal lead, and a sealing body made of sealing resin that seals the semiconductor chip, the signal lead and the wire. The signal lead has, in an extending direction of the signal lead, one end located inside the sealing body, the other end located outside the sealing body, and a wire connection region which is the main surface of the signal lead and to which the wire is connected, and an inner groove is provided in the main surface of the signal lead between the one end and the wire connection region.