The properties of domestic deproteinized natural rubber (DPNR) were studied, and its application in damping rubber products was investigated. The results showed that, compared with ordinary natural rubber (NR), the nitrogen content of DPNR was lower, the heat build-up in dynamic compression test was less, the compression set was smaller, the flexibility and electrical insulation properties were better, but the tensile strength and elongation at break were slightly lower, and the aging resistance was slightly lower. The rubber side bearing for locomotive by using domestic DPNR as the main material possessed good dynamic properties, enhanced fatigue resistance, excellent dimension stability, good elasticity, low heat build-up, low creep and small compression set.