Abstract: For the growing demand of heterogeneity and complexity of assembly design, the detailed geometry description and calculation are becoming more and more important. However the traditional equivalence theory cannot deal with the fuel pellet with fine meshes that limits the precise resonance calculation. As a result, a new resonance module with spatially dependent Dancoff method (SDDM) has been developed. Different from the traditional method, the SDDM method can split the fuel pellet into arbitrary number of annular, then calculate to get the effective cross section of every annular. By applying the SDDM, the new resonance calculation module has the capability to model and analyze the fuel in detail, as well as preserving the high calculation efficiency. The basic theory of SDDM was firstly illustrated in this paper, and then the effect and results of SDDM were also presented. The results show good accuracy and adaptability for the PWR.