PURPOSE: To make it possible to improve the utilization efficiency of a resin, to make it possible to prevent the generation of voids, breaks or the like in a packing part and to make it possible to shorten the exchange time of a metal mold by a method wherein a thermosetting resin material molded so as to coincide with the internal form of an oblong runner is sent by the application toward cavities by the use of a movable runner and the like.

CONSTITUTION: A thermosetting resin material 19 formed of a prescribed volume of resin is prepared so as to roughly coincide with the internal form of an oblong runner 5. After a mold opening is performed, lead frames are respectively positioned and held at sites of the upper surface of a plurality of cavities 15A formed via gates 6 at the positions in roughly line symmetry to the longitudinal direction of the runner 5. Then, the material 19 is put in the runner 5 and after a mold mold closing is performed, the material 19 is pressure-sent toward the cavities 15A and cavities 15B by a movable runner 1, which is driven in the runner 5, and a resin packing is performed. Then, after a mold opening is performed, an integrally constituted material consisting of the frames 3 subsequent to the end of the resin packaging is taken out outside of a metal mold.