To pull out the mold from a rubber molded item readily by integrally joining each part of a mold during the molding period of rubber molded items, and pulling them out from the opening of the molded item with each part of the inlying molds disassembled after completion.

An insertion rod is put into an engagement hole of an engagement piece exposed in the mold main body 2 from the opening 2b of the mold main body 2, thereby fastening the extrusion mold 3 at the side surface of the mold main body 2 for completing the mold. Next, an unvulcanized rubber sheet 11 is applied over the outer peripheral surface of the mold main body 2 and extrusion mold 3, and the joining parts 11a of each rubber sheet 11, 11 are adhered and vulcanized by an appropriate method such as vapor vulcanization, air vulcanization, or the like. Then, air is introduced from the upper end of a slender pipe 5, and allowed to spout outward of the bottom surface 2a of the mold main body 2 so as to be conducted between the whole of the mold and the molded item 10 for separating the whole of the mold from the rubber molded item 10. At this time, the extrusion mold 3 is dismounted from the mold, and the mold main body 2 is pulled out of the upper opening of the rubber molded item 10.