A lead frame of high quality which can endure direct bonding to the electrodes of a semiconductor element and a metal member, and a semiconductor device of high reliability which utilizing the lead frame. The lead frame includes a pair of lead frame portions which are arranged spaced apart from and opposite to each other to be electrically connected to a pair of electrodes of a semiconductor element respectively, and a pair of support bars which are arranged spaced apart from the lead portions and extending from a side of either one of the lead portions to a side of the other lead portion.