Synthesis of copper sulfide nanoparticles on the basis functionalized nitrile butadiene rubber (NBR-26) was carried out by the method of successive ionic layer adsorption and the reaction (SILAR). The reaction was undertaken at room temperature. The XRD records show well-formed nanocrystalline particles of copper sulfide as Cu1.8S with structure of cubic form. The crystallite size approximated 5 nm for Cu1.8S nanocrystals. The band gap of Cu1.8S nanoparticles is found to be 3 eV. SEM/EDX analyses showed that the synthesized materials are nanocomposites and the particle size of Cu1.8S is in the range of 9–12 nm. Infrared spectroscopy results illustrate that nanoparticles could grow on the –PO(OH)2 functional groups of polymer. The formed nanocrystals are quantum dots and can be used photoelectron transformation devices.