Development of artificial joints is a great progress for joint replacement operations of human being,but the short longevity of prostheses has conceed both industries and researchers since the advent of mode implants.Thus,continuous improvements have been made alongside the clinical applications.The methodologies to inspect the potential properties of new designs have also seen many advances.The test machines have evolved from easy pin-on-disk configuration to the mode joint simulator.Besides,various wear traces provided by testing machines are investigated greatly,and multi-directional files are recommended as motion profiles for in vitro testing.The typical testing parameters,like sliding speed or loading profile,are discussed in this article,and their working mechanisms are described in detail.Meanwhile,the calf or bovine serum has been regarded as the gold standard for testing lubricant,and the future trend of fluid will be focused on investigating the effects of lubricant composites on the tribological properties.Hard particles and proteins are discussed as well,and their effects on the wear mechanisms are the focus.Finally,various approaches to measure the wear rate,wear factor and the thickness of lubricant film are presented,and suggestions are given for the development in future.