Abstract: Disclosure is a metal mold for forming a transparent-resin-sealed semiconductor element which, when the molding is removed from it with knock-out pins, will not rub the molding mirror surface of the light transmitting window of the resin package, thus permitting the removal of the molding with the molding mirror surface maintained as it is. In the metal mold for a transparent-resin-sealed semiconductor element which is formed by sealing a semiconductor photo-electric element mounted on a lead frame in a rectangular-parallelepiped-shaped transparent resin package having a light transmitting window on its front end, the cavity surface of the upper die (a cavity block) which corresponds to the light transmitting window has a draft angle .theta.