The invention discloses a system for recycling waste heat of a nuclear power plant. The system comprises a nuclear power plant steam condenser (1) and further comprises a heat pump system (2) and a heat use system (3). The cooling water output end of the steam condenser (1) is connected with the input end of the evaporation side of the heat pump system (2), and the cooling water input end of the steam condenser (1) is connected with the output end of the evaporation side of the heat pump system (2). The hot water supply input end of the heat use system (3) is connected with the output end of the condensation side of the heat pump system (2), and the hot water supply output end of the heat use system (3) is connected with the input end of the condensation side of the heat pump system (2). The heat pump system is directly connected with a cooling water way of the steam condenser, closed circulation of cooling water is achieved, on one hand, recycling of the heat is achieved, and on the other hand, output of the heat is reduced, and heat pollution to the environment is avoided.