Abstract: There are many repetition structures in nuclear reactor cores, so the equivalent homogenization method was investigated. In order to make the linear relationship between the inflow and the outflow of the assembly boundary, the fission cross sections were divided by the k_eff of the reactor core, thus the eigenvalue problem was transformed into a fixed source problem. As a result, the coupling correlation of J⁺ and J^- could be decided by the linear coupling coefficients of them. Through iteration calculation in the reactor core, the k_eff of the reactor core and the boundary flows of every assembly could be worked out, and then the flux distribution was got. The C5G7 benchmark equivalent error was calculated and analyzed by using two dimensional S_N program SN2D. The results show that this method can get better k_eff and assembly power without group and angle merging, but the precision for pin power still needs to be improved in further studies.