The invention relates to the field of ship spraying robots, in particular to a using method of a spraying auxiliary device and a spraying robot. The spraying auxiliary device comprises a mounting transverse plate, and connecting side plates are arranged at the periphery of the mounting transverse plate. A driving mechanism for moving of the spraying auxiliary device is arranged on the mounting transverse plate. According to the using method of the spraying auxiliary device and the spraying robot, the structure of a traditional spraying robot is changed, through cooperation of a fixing mechanism, a first driving mechanism and a second driving mechanism, the spraying auxiliary device can better move on a hull, and the problem of difficult moving of a traditional spraying device on the hull is avoided; and meanwhile, through the spraying auxiliary device, spaying remote control operation on the outer facade of a large ship can be realized, the working efficiency is high, the labor intensity of workers is lowered, and paint has no effect on the workers.