Through determination and comparative evaluation of Kailuan fat coal and outsourcing 1/3 coking coal quality index, the possibility of mixing fat coal replaced by a small amount of 1/3 coking coal was studied. Based on the coal-coking method of 40 kg coke oven, the cold and hot strength of the coke, pore structure, apparent morphology and other parameters of coke were measured and analyzed emphatically. The results show that 1/3 coking coal and fat coal were  blended for coking, the former ratio should be controlled within 10%, the coke has no significant decline of CSR in this case, and the specific surface area and pore volume change a little, the apparent morphology of coke is no obvious deterinration.