Abstract: Neutron irradiation embrittlement of reactor pressure vessel (RPV) is the most important issue in nuclear safety, which affects the safety and economy of and public confidence in nuclear power plants. This paper introduces the traditional RPV irradiation surveillance method, discusses its limitations, combs the research progress and existing problems of RPV irradiation embrittlement non-destructive evaluation(NDE) technology, creatively puts forward a unified model for predicting the mechanical properties of RPV steel under neutron irradiation based on experiment and theoretical research, and forms a new NDE technology based on electromagnetic properties, which has a good engineering application prospects after further improvement. At the same time, this paper points out that the experimental study of electro-magnetic properties of RPV steel will not only help us to understand and recognize the irradiation embrittlement behavior of RPV steel in long service life, but also help to reveal the mechanism and enrich the basic theory of irradiation embrittlement.