Three kinds of nitrile rubberbased composites modified with different dimensions of carbon nanofiller,including carbon nanotubes (MWNT),multilayer graphene (MLG) and nanographite (NG),were prepared by solution blending method.The friction and wear tests were carried out on three kinds of composites under water lubrication and heavy load conditions.The tribological properties of the materials were compared with the test of friction coefficient,surface morphology and wear.The mechanism of carbon nanofillers with different dimensions was analyzed by SEM.The results indicate that the carbon nanofillers can significantly reduce the friction coefficient of nitrile rubber at low speed and improve its antiwear performance,among which the threedimensional nanographite has the best modification effect.The mechanism of three kinds of carbon nanofillers are as follows:onedimensional carbon nanotubes are easy to form physical crosslinking points with rubber molecules due to large aspect ratio,and play a role of micro bearing;twodimensional graphene is easy to fall off and transfer to form a good solid lubrication film to improve the friction and wear properties;threedimensional nano graphite can increase the adhesion and can reduce the phenomenon of interfacial debonding due to the intercalation of particle rough surface and rubber matrix.