Abstract: Based upon traditional PSA methodology used in full power condition and the features of NPPs (nuclear power plants) at shutdown operation, a specific approach to conduct shutdown PSA practically and feasibly is proposed. This Approach includes mainly discretization of POSs (plant operation states), phased evaluation and master plant logical fault tree. This feature approach is applied in shutdown PSA for GNPP, and some results and suggestions, which reflect the realistic situation of GNPP, are obtained. These recommendations and conclusions are of practical value to shutdown operation at GNPP and they are also of great significance for design, operation and management for other domestic NPPs.