A method for cycloaddition of dimethyl muconate is disclosed. According to the method, a direct transferring of a solid phase trans,trans-dimehtyl muconate into a reactor pre-filled with ethylene gas increases the efficiency of the reaction and suppress side reactions resulting an improvements in yield and purity. Furthermore, the method is capable of obtaining a high yield of dimethylcyclohex-2-en-1,4-dicarboxylate at a lower cost, and therefore is also useful for the mass synthesis of dimethyl terephthalate.