In a method of sealing electronic parts with molded resin, a hollow sealing member is arranged on a mold surface of an upper mold section of a mold comprising the upper mold section and a lower mold section, so that the hollow sealing member is pressurized and expanded to convexly project from the mold surface of the upper mold section. In this state, the lower mold section is upwardly moved to be brought into contact with the expanded hollow sealing member. Further, an internal space portion, including pots, cull portions, resin passages and cavities, which is enclosed with the expanded hollow sealing member is set in a state isolated from the exterior when the upper mold section and the lower mold section are closed, so that the internal space portion is forcibly evacuated in this state. Thus, air, moisture and gases are efficiently and reliably suction-discharged from the internal space portion, whereby the internal space portion is set at a prescribed degree of vacuum. Consequently, it is possible to avoid contamination of air, moisture and the like in melted resin materials, as well as to prevent formation of voids in resin-sealed compacts.