Epoxidized liquid natural rubber with 25 percent mol epoxide content was prepared by reacting phenylhydrazone terminated liquid natural rubber with 3-chloroperbenzoic acid. The reaction between isoamyl alcohol and epoxidized liquid natural rubber catalysed by cerium ammonium nitrate was achieved in dichloromethane solution at 30°C. Structure of polymers was determined by 1H-NMR and 13C-NMR, thermal stability of polymers also was investigated by thermal gravimetric analysis (TGA). The results showed that the epoxide ring opening epoxidized units lead to the formation of hydroxyl and isoamyl groups and thermal stability of product is lower than epoxidized liquid natural rubber.