Disclosed is a semiconductor device comprising a lead frame which includes a metal layer forming an outer lead, a thin metal layer forming an inner lead, an intermediate layer held between the thick metal layer and the thin metal layer for forming a connection portion between the outer lead and the inner lead and a bump positioned at the extreme end of the lead frame, whereby making the lead frame as an electrode leading means by directly connecting the bump to each electrode of a semiconductor element, wherein the lead formed of the thick metal layer has a thickness of 30 to 300 .mu.m, the lead formed of the thin metal layer has a thickness of 10 to 50 .mu.m, and the bump has thickness of 5 to 50 .mu.m.