[Objectives] The switching performance of turbine feed water pump is a key technical indicator to decide the operation stability of ship steam power system, and it is of great significance to the safety of navigation.[Methods] Using the Modular Modeling System(MMS) thermal engineering system simulation software, a simulation model of ship steam turbine power system based on the switching principle of turbine feed water pump is established. Meanwhile, the accuracy of the simulation model is verified by experiment data. The dynamic response of turbine feed water pump to steam-water cycle of steam turbine power system is analyzed under high-speed and low-speed conditions.[Results] The calculation results show that switchover of turbine feed water pump can meet the water supply demand of supercharged boiler under high-speed and low-speed conditions. After switching, the system can run stably under low-speed condition, but the operation of the system is unstable after switching under high-speed condition. It shows that the water level of the condenser rapidly rises to an extremely high level, and the water level of the deaerator drops sharply to an extremely low level. Severe pressure fluctuation occurs in exhaust steam and micro superheated steam.[Conclusions] The research results can provide theoretical support for the optimization of the switching scheme of the steam turbine feed water pump.