The invention discloses a waste heat discharge pump for a nuclear power plant, which comprises a stator component, a rotor component, a bearing component and a shaft seal device. The stator component comprises a pump casing, guide vanes arranged in the cavity of the pump casing, a pump cover connected at the front end of the pump casing and a sealing box body connected at the front end of the pump cover. The rotor component comprises a pump shaft and vane wheels sleeved on the pump shaft through vane wheel nuts and located in the cavities of the guide vanes. The bearing component comprises a bearing body, bearing pressing covers, a driving end bearing and a non-driving end bearing, wherein the front portion and the rear portion of the bearing body are respectively provided with bearing cavities, the bearing pressing covers are covered at two ends of the bearing body, and the driving end bearing and the non-driving end bearing are arranged in the bearing cavities one by one. The shaft seal device is a containerization balanced type single end face mechanical seal and is arranged in the cavity of the sealing box body. The rotor component further comprises a retainer gasket which is arranged between the vane wheel nuts and the vane wheels in a mode that a tongue piece of the retainer gasket is covered on the planes of the vane wheel nuts. The bearing component further comprises a cooling water jacket and a cooling water pipeline, and a bearing protector is respectively arranged in cavities of the bearing pressing cover at two ends.