The study prepared high-performance ultra-high molecular weight polyethylene/graphite fluoride (PE-UHMW/GrF) composites using ball milling and hot pressing techniques. The wettability, mechanical properties, and tribological performance of composites in a water-lubricated environment were studied by a contact angle measurement equipment, a tensile testing machine and a friction-wear testing machine, respectively. The results showed that the addition of graphite fluoride (GrF) significantly reduced the hydrophilicity of the composites. Adding a small amount of GrF significantly improved the mechanical properties of the composites. When the mass fraction of GrF reached 1.0%, the elastic modulus, yield strength, and tensile strength of the composites increased by 39.13%, 15.19% and 6.60% compared to PE-UHMW. In the water-lubricated environment, GrF reduced both the friction coefficient and wear rate of the ultra-high molecular weight polyethylene (PE-UHMW) matrix. With a 0.5% mass fraction of GrF, the friction coefficient of the composite dropped to a minimum value of 0.023 3. GrF enhanced the wear resistance of the PE-UHMW composites, with the wear mechanism primarily being fatigue wear. With the GrF content increased, the fatigue wear resistance of the composites progressively improved.