A carbon fiber-reinforced polyetheretherketone (PEEK) composite acetabular cup was fabricated by injection molding. An extensive hip joint simulator test was conducted to evaluate the tribological performance of this CF-PEEK composite cup as a potential orthopaedic bearing surface. Hip joint simulator testing up to 10 million cycles showed that the wear of the composite cups is about 1% that of the UHMWPE cups. Hertzian contact stress analysis indicated that the CF-PEEK material had a lower maximum contact stress/yield strength ratio compared to air-irradiated UHMWPE acetabular cups. With prudent application of composite design principles, it is possible to engineer a composite insert that shows promise as an orthopaedic implant bearing surface in total hip replacements.