The start-up of the fire pump is the most important link of the water fire extinguishing system of fire protection. How to effectively start the fire pump to ensure the reliability of fire extinguishing, the specification gives multiple guarantee measures, including on-site manual start-up of the pump room, mechanical emergency start-up, remote start-up of the fire control room, and linkage programming start-up of the automatic fire alarm system. However, it is always controversial to start the fire pump with the flow switch of the roof fire water tank. This paper discusses and studies that starting the fire pump with the flow switch is unnecessary through the engineering example of the high-speed railway station.