β-Caryophyllene- maleic anhydride copolymer (BCPMA) was synthesized by using β-caryophyllene and maleic anhydride as raw material with di-tert-butyl peroxide (DTBP) as initiator and cyclohexanone as solvent.The effects of reaction temperature, reaction time, molar ratio of monomers, the amount of solvent and the amount of initiator on the yield of the copolymer were discussed. The structure of the polymer was characterized by FTIR, 1HNMR, GPC and elemental analysis. Thermal stability of the polymer was determined by thermal gravimetric analysis (TG).The results show that when the conditions of reaction temperature 145℃, reaction time 1h, molar ratio of maleic anhydride to β-caryophyllene 2:1, mass ratio of cyclohexanone to β-caryophyllene 2:1 and initiator dosage 4.5%, the yield of copolymer can reach 92.9%. The initial decomposition temperature of the copolymer is 370.6℃, which indicates that it has high thermal stability.