A method for manufacturing a lead frame including: punching a metal plate disposed on a die with a punch in a direction from the metal plate toward a die side to form a punched metal, the punched metal including at least one electrode, at least one hanger lead separated from the at least one electrode, and an outer frame connected to the at least one electrode and the at least one hanger lead; and stamping at least part of a corner of an end of the at least one hanger lead, the corner being on a side corresponding to the die side, with a vertically split mold to form at least one chamfered surface.