Abstract: The metal reflector is influenced by irradiation and heat flow in the reactor pressure vessel, thus its temperature analysis is a complicated thermal-fluid-structure coupling problem. In order to simulate the temperature distribution of the metal reflector more accurately, the heat generation rate caused by irradiation is taken into account. Then a method based on thermal-fluid coupling and thermal-structure coupling is proposed in this paper. The method utilizes an iteration of fluid steady-state thermal analysis and structure steady-state thermal analysis to compute the temperature distribution of the metal reflector and the natural convection heat transfer coefficient. Compared with the results of the existing method, the results of the method in this paper is more reliable for more boundary conditions are applied in the calculation.