PURPOSE: To obtain molded small sized cylindrical parts made of resin, which require no after processing and is capable of maintaining high accuracy, by a method wherein molding is made by supplying molten resin through a ring gate having a larger inside diameter than those of cylindrical parts.

CONSTITUTION: Molten resin is supplied to the inside of a movable cavity 13 through a ring gate 26. After solidification of the resin, a movable side receiving plate 11 is lowered by acting a movable part, a stationary side die plate 24 is pressed by a kicker pin 31 through bounce of a spring 32, the stationary side die plate 24 is separated from a stopper plate 30 and the ring gate 26 is cut off. In succession to the above, when the movable side receiving plate is lowered and the stationary side die plate 24 and the movable side die plate 12 are lowered until they are abutted against a head part 34b of a stopper pin 34 and a head part 35b of a stopper pin 35 respectively, appropriate gaps are kept among the stopper plate 30, the stationary side die plate 24 and a movable side cavity 12. Then, the stopper plate 30 is lowered and a part of a runner sprue 40 made of resin is taken off forcibly. An ejector pin 15 is protruded by lowering the movable receiving plate 11 further and molded cylindrical parts 10 are pushed up to the upper part of the movable side cavity 13.