The invention provides a CSP type semiconductor device with high reliability. The semiconductor device includes a pad electrode (4) formed on a semiconductor substrate (1), a first passivation film (5) covering an end portion of the pad electrode (4) and having a first opening (6) on the pad electrode (4), a plating layer (7) formed on the pad electrode (4) in the first opening (6), a second passivation film (9) covering an exposed portion of the pad electrode (4) between an end portion of the first passivation film (5) and the plating layer (7), covering an end portion of the plating layer (7), and having a second opening (10) on the plating layer (7), and a conductive terminal (11) formed on the plating layer (7) in the second opening (10).