The invention is suitable for the field of million kilowatt level pressurized water reactor nuclear power station control, and provides a method and a system for monitoring temperature of generator stator windings of a nuclear power station. The method comprises: acquiring operation parameters of the stator bars in a present operation condition of a generator; and mapping outlet water temperature of the stator bars in the present operation condition of the generator to outlet water temperature of the stator bars in a reference operation condition of the generator, and obtaining outlet water temperature mapping values of the stator bars in the present operation condition of the generator. The method eliminates influence of the generator operation condition on the outlet water temperature of the stator bars, so monitored temperature of each stator bar reflects practical temperature state of each stator bar in a more real and accurate manner, and heat faults of the generator stator winding can be monitored accurately in time.