PURPOSE: To enable a high quality and high reliability resin sealing molding to be manufactured with high efficiency by applying required vibration to a plunger during the time of pressurizing period of a resin material by the plunger, and applying a required vibration effect to be resin material via the plunger.

CONSTITUTION: A lead frame mounted with electronic parts is set on a predetermined position in the P.L surface of a lower mold 2, and resin materials R are supplied respectively into the each spot 3 of the lower mold 2, and the mold clamping of both upper and lower molds is conducted then. At this time, a load meter 18, vibrator 10, disengaging member 9, plunger holder 7 and respective plungers 4 move upward simultaneously. And, in the time of resin sealing mold, the vibrator 10 is actuated at least when each plunger 4 pressurizing respectively the resin materials R within the each spot 3 moves upward, and each of plungers 4 receives a predetermined vibration via the plunger holder 7.