The invention discloses an automatic checking method for a protection device. The method comprises steps: channel name matching is firstly carried out according to a channel naming rule; recording records of a recording acquisition unit are matched within 5 minutes before and after recording starting of the protection device, the analog amplitudes and the switch states at the first 20 ms and the last 30 ms are compared according to a starting zero time in a recording file, and A, B, and C three-phase data comparison is carried out sequentially; and finally, according to a data comparison result, a checking result of the protection device is given. The automatic checking method for the protection device solves discrimination of behavior effectiveness of the protection device in an intelligent substation, an abnormal protection device is positioned quickly, hidden dangers of the protection device can be found out in advance, and extremely important practical significance is achieved.