Abstract: The coal mine underground gangue discharge and gob filling technology is an effective way to realize green miningThe control system of mechanical moving sieve jig is the core equipment of the underground coal preparation system，and the performance is critical to improve the efficiency of separationAs the features of control system are nonlinear timevarying uncertainties and pure lag，the fuzzy logic control is designed for jig control system to fuzzy controlling speed of discharging motorIndustrial test was carried out in Tangshan coal mine，and three type of inputs were tested to obtain relationship between the amount of coal gangue in movable sieve and the motor frequencyThe experiment results showed that the fuzzy logic control was found to be more efficient for stabilizing the gangue layer than other control system，which could avoid the destruction of gangue layer structure and improve the efficiency of coal and gangue sorting，which can achieve the ideal effect of gangue discharge