The invention relates to the technical field of chlorine, and discloses a device for controlling reaction speed in chlorine production, the device comprises a base, the upper surface of the base is fixedly connected with a reaction box, and the upper surface of the reaction box is fixedly connected with a shell. According to the device for controlling the reaction speed in chlorine production, through the arrangement of the motor, the transmission rod, the gear, the toothed plate, the conductive rod and other structures, the motor is started to drive the gear to rotate forwards, the gear drives the conductive rod to move through the toothed plate, the distance between the positive electrode rod and the negative electrode rod can be increased, the length of the conductor is reduced, resistance can be reduced and current can be increased, the electrolysis rate of the solution and the production rate of chlorine are improved; in a similar way, the motor is started to drive a gear to rotate reversely, and the distance between the positive pole rod and the negative pole rod is reduced, so that the chlorine production rate can be reduced, the chlorine production rate can be effectively controlled by the device, and the device is convenient to use by workers; and the practicability of the device is enhanced.