The invention relates to a novel feed water pump system and an operation method thereof. The novel feed water pump system comprises a feed water pump turbine, a high-speed clutch, a steam-driven feedwater pump, a hydraulic coupler and a motor; one end of the high-speed clutch is connected with the feed water pump turbine; the steam-driven feed water pump is connected with the other end of the high-speed clutch, when the high-speed clutch is engaged, the feed water pump turbine is connected with the steam-driven feed water pump through the high-speed clutch and drives the steam-driven feed water pump to rotate, and when the high-speed clutch is disengaged, the feed water pump turbine is separated from the steam-driven feed water pump, and the feed water pump turbine stops driving the steam-driven feed water pump to rotate; one end of the hydraulic coupler is connected with the steam-driven feed water pump; and the motor is connected with the other end of the hydraulic coupler, and whenthe hydraulic coupler is engaged, the motor is connected with the steam-driven feed water pump through the hydraulic coupler and drives the steam-driven feed water pump to rotate. According to the novel feed water pump system, water feed pipelines and valves of a water feed system are reduced, the system configuration is simplified, and the safety of the water feed system is improved.