PURPOSE: To provide an injection mold superior in reproducibility of a position and inclination of a movable side lens core.

CONSTITUTION: A base end part of a movable side lens core 5 forming a molded product 6 is fixed to a knockout bar 7. A female side tapered pin 8a is provided on the surface of the knockout bar 7 facing on a movable retainer plate 4. On the one hand, the movable retainer plate 4 is provided with a male side tapered pin 8b which is fitted in the tapered pin 8a at the time of molding. Hereby, position of a movable side lens core 5 becomes fixed at the time of the molding. A positioning mechanism 9 is provided by penetrating through a moving plate 1 and the movable retainer plate 4. Hereby, even if a mold is reassembled, a positional relation between the moving plate 1 and movable retainer plate 4 is fixed, consequently misregister is not generated on the movable side lens core 5.