The invention discloses a cleaning device for gear machining. The cleaning device comprises a cleaning table face, the lower side of the cleaning table face is connected with a lifting column, the bottom end of the lifting column is connected with a hydraulic cylinder, the cleaning table face is arranged on the inner side of a water tank, the inner walls of the left side and the right side of thewater tank are provided with ultrasonic wave cleaners correspondingly, the upper side of the water tank is provided with a support, the bottom end of the support is fixedly connected to the water tank, a rotating shaft is vertically arranged on the center of the upper side of the support, the bottom end of the rotating shaft is connected with a horizontally-arranged brush handle, and a cleaning brush is fixedly arranged on the lower side of the brush handle. According to the cleaning device for gear machining, circulating spraying, lifting brushing and ultrasonic wave cleaning are adopted forcleaning a gear, the cleaning effect is good, the efficiency is high, manual operation is not needed, the labor intensity is lowered, resources are saved, the using cost is reduced, moreover, a casting can be subjected to air drying after being cleaned, casting rusting is effectively avoided, vibration produced by the device can be reduced in all directions, noise is reduced, safety is improved, and the service life is prolonged.