Based on a large number of similar irradiation embrittlement test data and actual radiation monitoring test data, a formula for evaluating the irradiation embrittlement of the reactor pressure vessel (RPV) of a nuclear power plant is selected using the method of statistical analysis. The irradiation supervision tube test data of the nuclear power plant has been completed as input data, and the present irradiation embrittlement status of RPV was evaluated. The structural integrity of RPV at the end of life was calculated and analyzed. Based on the calculation results of irradiation embrittlement, the
P-
T curves of RPV in each operation stage are plotted, and the operation suggestions are given.