Abstract: An automatic identification system of coal and gangue for fullly-mechanized coal caving working face based on vibration signal was proposed, structure and working principle of the system were introduced and design schemes of software and hardware of coal and gangue identification device were expounded as well as identification algorithm. The coal and gangue identification device identifies coal and gangue according to different vibration signals of coal and gangue falling on hydraulic support. Electro-hydraulic controller controls hydraulic support act according to identification result. The system has been tested with contents of identifiability of coal and gangue and controllability of automatic coal caving process in a mine and applied in some mines, which gets better effect.