The utility model discloses a rubber cylinder positioning device, belongs to the field of cigarette making equipment and particularly relates to the rubber cylinder positioning device which is used for solving the phenomenon that a rubber cylinder is not installed in place. The rubber cylinder positioning device comprises the rubber cylinder and a rubber roller arranged on the rubber cylinder, wherein a gear is arranged at one end of the rubber roller; a left rubber cylinder positioning block and a right rubber cylinder positioning block are arranged on the rubber cylinder; a cone-shaped groove which is matched with a conical surface of a positioning pin is formed in the plane of the left rubber cylinder positioning block; and a V-shaped groove which is matched with the conical surface of the positioning pin is formed in the plane of the right rubber cylinder positioning block. In the rubber cylinder positioning device, the conical surface of the positioning pin is matched with groove surfaces of the positioning blocks, so that the contact is closer, the stability of the rubber cylinder is increased, and then the phenomena that the ends of cigarettes drop off and the cigarettes have poor air tightness are avoided.