Objective To compare the method based on computational fluid dynamics (CFD) and fluid structure interaction (FSI) with the traditional Reynolds equation method in the study of an artificial hip joint lubrication system. Methods Using business software Adina as a computing platform, the metal-on-metal total hip replacement (MOM THR) model was developed as the subject to establish the rigid and elastic CFD model, respectively. Results The film- thickness curve obtained by the CFD&FSI method had a significant depression in the center, which was more reasonable than that obtained by the traditional Reynolds equation method. The model with elastic surface under the given load showed a significant deformation at the FSI surface of the acetabular cup femoral head, and the deformation was consistent with the pressure and film thickness distribution in fluid field. Conclusions The CFD&FSI method used here was more reasonable than the traditional method when computing the elasto-hydrodynamic lubrication of an artificial hip joint system.