The utility model relates to a power generation facility technical field, saying more specifically, it relates to a generator centrifugal pump water injection device, and its technical scheme main points are including setting up the siphon jar in the pond top, vertical direction runs through and is provided with the siphon in the siphon jar, the siphon extends to below the liquid level of pond, siphon tank deck end is opened has the water injection hole that is used for the staff to carry out the water injection in to the siphon jar, be provided with the water injection flange that is used forsealing the water injection hole on the water injection hole, the lateral wall intercommunication of siphon jar has the inlet tube, the other end of inlet tube is connected with the centrifugal pump,the intercommunication has the outlet pipe that is used for following water siphon jar suction to generator on the centrifugal pump, be provided with the driving piece of drive centrifugal pump workon the centrifugal pump. This generator centrifugal pump water injection device has solved the problem of the sail difficulty that the centrifugal pump arranged in pond liquid level top meets at everyturn when starting.