Abstract: The feasibility study of 18-month fuel management of 157 core was carried out by using the gadolinium rod optimization technique. The Equilibrium Cycle fuel management of gadolinium rod optimization scheme was designed, and the main calculation results of the base scheme and gadolinium rod optimization scheme were given. The results show that the gadolinium rod optimization scheme can meet the design criteria of 18-month refueling cycle operation by rationalizing the arrangement of fuel assemblies and burnable poison. In the same cycle length, the average discharge burnup of the core with gadolinium rod optimized fuel management design is higher, the fuel usage cost is less, and the economy is better.