Carbon fiber (CF) and nano-silica (nano-SiO₂) particles were employed simultaneously to modify polyoxymethylene (POM). Our goal was to control the distribution and dispersion of CF and nano-SiO₂ particles in POM matrix using an appropriate processing method and adjusting the dispersion of nano-SiO₂ particles toward CF and POM, so as to achieve a simultaneous enhancement of toughness and modulus of POM. The results of tribological tests showed that the POM with 3 vol% nano-SiO₂ presented better tribological properties. When the content of nano-SiO₂ was not more than 3 vol%, the CF/POM/nano-SiO₂ samples presented lower friction coefficients and smaller wear volumes. However, higher contents of nano-SiO₂ than 3 vol% were very disadvantageous to the tribological performances.