PURPOSE: To prevent surely lead frames from being deformed because of clamping pressures by applying the clamping pressures of upper and lower molds to the lead frame sides of a metallic semiconductor when resin sealing is molded.

CONSTITUTION: A range W is required by: a semiconductor element 1 which is set in cavities 5 and 6; inner leads 2; and base end parts of outer leads 4 and the like holding positions which are more inward than those of the tie bars 7 of metallic lead frames and its range is sealed and molded in a resin compact B which is molded according to forms of the cavities 5 and 6. Resin moldings are manufactured through a process of cutting the tie bars 7 from frames 8 so as to divide them into separate ones as well as the process and the like which bend the pointed end sides of the leads 4 into the required shapes. In such a case, clamping pressures of upper and lower molds are applied to the lead 4 sides in the frames 8. This approach surely prevents the leads frames 8 from being deformed by the clamping pressures.