Abstract: The safety of the floating nuclear power plant is closely related to the merits of the reactor power supply system. In order to improve the safety factor of floating nuclear power plant, it is necessary to analyze the reactor power supply system. In this paper, the configuration of the reactor power supply system of the floating nuclear power plant is analyzed, and the auxiliary power system and nuclear emergency power system under two schemes are compared. The results show that the optimized scheme 2 is better than scheme 1 in reliability and safety, and scheme 2 is more economical. The optimization scheme proposed in this paper can provide a direction for the design of the reactor power supply system of the subsequent nuclear powered ships and has a strong reference significance.