Abstract: In order to solve the problem of easy sliming of coal series cray rock in the process of coal processing, the change law of pore structure of coal series clay rock under different electrolyte concentration was investigated by low temperature liquid nitrogen adsorption method. The relationship between the pore structure characteristic of coal series clay rock and its sliming was analyzed, and the structural mechanism of electrochemical inhibition of coal series clay rock sliming was revealed. The results show that electrochemistry can change the pore type of clay rock, and significantly reduce specific surface area, pore volume and pore fractal dimension of clay rock. It can also reduce micropore ratio of clay rock, and can increase its average particle size. The change of pore structure characteristic of clay rock would weaken their hydration properties, which would cause the sliming process of clay rock to be effectively inhibited.