A molding die has a lower holder, an intermediate holder, an upper holder, a lock member, an upper link bar, a lower link bar, a restriction member, and a drive part. A movement of the lock member in a molding die opening direction or a molding die closing direction is restricted by the intermediate holder. The upper link bar has a first retaining groove in which the lock member fits when being located at a molding die closing position. The lower link bar has a second retaining groove in which the lock member fits and a release portion that enables the lock member to be released from the first retaining groove. The restriction member is movable between a restriction position that prevents the lock member from fitting in the second retaining groove and a free position that enables the lock member to fit in the second retaining groove.