To improve the friction and wear behavior of hydrogenated nitrile butadiene rubber (HNBR) composites, graphite and silane-treated Silicon carbon (SiC) were incorporated. The tribological properties of the resulting composites were investigated systematically on a model ball-on-block test rig. The friction and wear mechanisms of the composites were studied through analyzing the worn surfaces by a scanning electron microscopy. Experimental results showed that the friction and wear behavior of the filled composites were improved greatest when graphite and silane-treated SiC were added together, indicating that there was a synergistic effect between them.