Wear of total hip is a significant clinical problem that involves, nowadays, a large number of patients. In order to acquire further knowledge on the tribological phenomena that involve total hip, wear tests are conducted to evaluate the possibility of extending its lifetime. The most basic type of test device is the wear testing machine, and nowadays, this type of machine may more accurately reproduce some of the in vivo conditions, then is also called simulator. The simulator is designed to simulate movements of the total hip, which consist of flexion - extension, abduction - adduction and inward - outward rotation, under the conditions rather similar to those occurring in human body. Its specifications and the test process must be assured the requirements of ISO 14242 standard.