A lead frame includes a first electrode, a second electrode, two hanger leads, and an outer frame, and partially forms a box-shaped package which has a first recess for mounting a light emitting element as combined with a support member that supports the first electrode and the second electrode. At least a portion of lower faces of the electrodes, at least a portion of lower faces of the hanger leads, and at least a portion of a lower face of the planned formation area for the support member are coplanarly formed. Lower face corners of the first electrode and the second electrode are rounded while upper face corners of the first electrode and the second electrode are not rounded, and upper face corners of the hanger leads are rounded while lower face corners of the hanger leads are not rounded.