The goal of this project is to derive the hydrodynamic lubrication model of ultrahigh molecular-weight polyethylene (UHMWPE) used in total joint replacement. The effect of hydrodynamic lubrication film to study different types of lubricants and geometry parameters of surface pattern, and carry on the hydrodynamic wear experiments to understand that macroscopic friction coefficient is to the influence of hydrodynamic lubricated. The experiment instruments will be used to pin-on-disk test. The friction coefficients will then be obtained and the experimental data will correlate with each other. The relationship between friction coefficients of experiment and the hydrodynamic lubrication pressure will be investigated. Since the lubricants also play a very important role in the interface, the lubricant pressure and film thickness effects between two contact surfaces due to lubrication will also be included in the contents. Both theory and experimental approach are elaborated in the proposal. Hopefully, through the ongoing project, several alternatives to reduce the interface friction such as specific surface pattern and lubricant application could be proposed at the end of the project.