Provided is a semiconductor device including a package having a hollow portion, which can meet the need of reduction in size and thickness. The semiconductor device includes: a resin molded member (1) including a hollow portion (10) having an inner bottom surface on which a semiconductor chip (6) is mounted, a surrounding portion (1b) that surrounds the hollow portion (10), and a bottom surface portion (1a); an inner lead (2e, 2f); and an outer lead (2a, 2b) exposed from the resin molded member (1). The inner lead buried in the molded member (1) includes an L-shaped lead extending portion having a through hole formed therethrough.