Objective To numerically simulate the motion characteristics of red cells in shear flow, so as to provide theoretical references for exploring pathogenesis of cardiovascular diseases and conducting experimental studies of blood circulation. Methods The hyper-elastic model of red cells with membrane thickness was established. Based on feedback force method and finite element immersed boundary method, the deformation and motion of red cells in shear flow were simulated. The solid was defined as being hyper-elastic and solved by finite element method, while the fluid was defined as incompressible Newton fluid and solved by finite difference method. Results The tank tread-like motion characteristics of red cells in shear flow were gained by numerical simulation. The simulation results in the study were consistent with the results in the literature, which validated the reliability of the proposed method in the study. Conclusions The immersed boundary method adopted in the study shows obvious advantage in solving the large deformation problem by preferably demonstrating the whole process of red cell deformation in shear flow.