Abstract
With the research and application of Significance Determination Process (SDP) in China, it is urgent to carry out the detailed analysis of the significance of abnormal events at power, especially the NRC reactor regulation concept is being accepted to regulate the nuclear power plant in china. Based on Significance Determination Process (SDP) and the actual case analysis, this paper analyzes the significance of license operation event in a nuclear power plant with the current developed PSA model. The analysis process includes the initial significance determination, detailed analysis and external events/LERF analysis, finally determine the significance of license operation event, and provide a reference for the subsequent analysis of abnormal events.