Abstract: Resonance calculation must treat global and local effects, namely, the interference among different pins, the interference among different nuclides, nuclide distribution effect and temperature distribution effect. The conventional resonance method cant exactly solve all the problems, simultaneously. This paper uses pseudo isotope method to treat the interference effect among different nuclides with high precise and efficiency. According to the assessment of the generalized equivalence theory, a high-fidelity resonance calculation method is proposed. In order to incorporate the global effect, the iteration calculation is performed for the U-238 based heterogeneous table. After the background cross sections for different fuel pin are obtained, the interpolation of the table is carried out to find an equivalent pin. Then the ultra-fine calculation is carried out on the equivalence pin based on the real nuclide composition and temperature distribution to get the high-fidelity effective cross sections for the nuclide at different position in the fuel pin.