Nitrile rubber latex was prepared by conventional emulsion polymerization combined with low-temperature batch polymerization process, the latex was hydrogenated with self-made ruthenium catalyst, and the influence of catalyst amount and hydrogen pressure on the hydrogenation effect of nitrile rubber latex was systematically studied. The results showed that the average particle size of the prepared nitrile rubber latex was 69.13 nm, and the particle size of the latex remained basically unchanged and the latex remained stable before and after hydrogenation. The higher the hydrogen pressure was, the better the catalytic hydrogenation effect was. When the mass fraction of catalyst was 0.017 5%, degree of hydrogenation of the product was more than 99% and no gel was obtained.