The tribological behavior of poly(ether ether ketone) (PEEK) composites was investigated using a universal micro-tribotester under dry friction conditions. We studied the effect of addition concentration, applied load, and sliding speed on the friction and wear behavior of composites filled with multi-walled carbon nanotubes (MWNTs), graphene oxide (GO) nanosheets, and gamma-aminopropyl trimethoxysilane-modified graphene oxide (GO-Si) nanosheets. The results showed that the friction reduction and anti-wear performance of PEEK composites filled with GO-Si is the most effective, that of the composites filled with GO is the next, while that of the composites filled with MWNTs is the worst. GO-Si-filled PEEK nanocomposites have the best friction reduction and anti-wear properties when the applied load and the sliding speed are 2.94 N and 0.0628 ms(-1), respectively. Furthermore, scanning electron microscope (SEM) investigation showed that GO-Si-filled PEEK composites had smooth worn surface under given applied load and sliding speed, and well-dispersed GO-Si in PEEK matrix provided a large surface area available for interaction between polymer molecules and GO-Si, which helped to reduce the wear of PEEK composites.