Waterproof box locking device

The utility model relates to a waterproof box locking device. A waterproof box consists of an upper box body and a lower box body which are closed correspondingly, a waterproof ring is arranged between the upper box body and the lower box body, the locking device comprises a fastening groove and a lock catch which are correspondingly arranged on the upper box body and the lower box body, one sideof the fastening groove is equipped with a valve penetrating through the box, the lock catch is arranged on the box in swinging form and equipped with a fastening hook and a valve switch, wherein thefastening hook is in corresponding fastening connection with the fastening groove, and the valve switch can correspondingly press and close the valve. When the lock catch is pressed and locked, the valve switch on the lock catch is just right pressed into the valve and enables the same to be closed, and then the upper box body and the lower box body of the waterproof box are completely locked andsealed. When needing to ope