Abstract: In order to solve the problem of bad reliability of data transmission of wireless communication system of coal mine underground because the system's parameters such as carrier frequency,modulation mode are settled and so it ca't adapted to change of tunnel's channel model,the paper proposed a scheme of applying cognitive radio technology in wireless communication system of coal mine underground.The cognitive radio technology can perceive frequency spectrum and channel model of tunnel through which radio signal of communication system passes,and real-timely and self-adaptively adjust some transmission parameters such as carrier frequency,modulating mode and so on,so as to optimize transmission performance of wireless communication network of coal mine underground.The paper comprehensively analyzed the feasibility of cognitive radio applied in coal mine underground too.At last,it concluded concrete realization mode of cognitive radio applied in coal mine underground.