Oxidized cellulose nanocrystal (OCNC) prepared by H2O2 served as anchorage sites of combined Zn2+-carboxylate bonds and curing agent precursor for fabricating XNBR/OCNC/ZnO composite via in situ interfacial reactions. The novel cross-linking by OCNC influenced on the microstructure, morphology, and properties of the composites were characterized. The cross-linking of Zn2+-carboxylate networks endow the composites to achieve 295% and 200% increases in tensile strength and cross-linking density, excellent wear resistance (90% reduction in relative mass loss compared to neat XNBR), irradiation aging resistance, respectively. This study provides a universal, simple and scalable method for the fabrication of multifunctional rubber composites by constructing Zn2+-carboxylate cross-linked network with natural cellulose resources.