The invention discloses a method for deploying and reusing disc and angular gears. The method comprises the following steps of: (1) selecting materials: selecting gears without defects from the waste disc and angular gears, washing the same-model disc and angular gears produced by the same manufacturer with washing oil, and drying the same-model disc and angular gears in air; (2) assembling: assembling the disc and angular gears dried in air on a differential case, regulating gaps, coating a layer of inkpad on two-sided disc gears which are in force-bearing contact, and requiring running-in and regulating if a stress surface is small and inkpad is a little; (3) carrying out running-in: reducing gaps of differential disc and angular gears which need running-in and regulating, carrying out running-in, and regulating running-in time according to amount of the inkpad on the disc and angular gears; (4) cleaning: dismounting the run-in disc and angular gears, cleaning the run-in disc and angular gears and drying the run-in disc and angular gears in air; and (5) deploying: re-assembling the disc and angular gears dried in air on the differential case, and regulating the gaps. The method disclosed by the invention is simple to operate, is convenient and practical, and changes waste into things of value.