Abstract: Nuclear robots play a very important role in safe operation of nuclear power plants.In this paper,the operating principle of nuclear power plants is firstly introduced and the safety levels of key nuclear facilities are illustrated.Then the present research status of nuclear robots in the world is summarized from three main aspects:maintenance of key nuclear facilities,inspection and warning of nuclear radiation,accident management and rescuing.Finally,the key technologies of nuclear power plant robots are discussed,and the research prospects are presented.