Objective To study the patterns of stress distributions on the area around the acetabulum during normal gait cycle, and to further explore the distribution of biology force lines of each column of the acetabulum as well as the thickness morphology of cortical bones. Methods The muscle and hip loads under 8 typical phases of human gait cycle were obtained through human reverse dynamics analysis. The three-dimensional (3D) model of hip joint was built by 3D reconstruction technology, and the finite element analysis and topology optimization of cortical bones were conducted by using the obtained loads as loading boundary conditions. Results In support phase, the hip joint load was larger, the strain energy of the middle column accounted for 55% -69% of the total strain energy, and the stress at top of the acetabulum was larger. In swing phase, the hip joint load decreased and the percentage of strain energy in the middle column decreased. Different motion angles of the hip joint affected muscle forces and further affected stress distributions on hip joints. The obtained biology force lines of each column of the acetabulum based on finite element method were basically consistent with biology force lines and bone trabecular arrangement proposed by the anatomy, and corresponded to thicker areas of cortical bones in topology optimization simulation results. Conclusions Biology force lines of each column of the acetabulum and thickness morphology distributions of cortical bones can be determined by numerical simulation, which provides theoretical references for reasonable placement of the internal fixation for fracture treatment.