Diethylstilbestrol monocarboxymethoxyflurane (DES-MCME) was synthesized by first retouching a phenolic hydroxyl group of DES molecule and using diethylstilbestrol;sodium monochloroacetate and bovine serum albumin as key raw materials.The conjugations of DES-MCME with proteins as a complete antigen were prepared by the mixed acid anhydride method and the conjugations were analyzed by ultraviolet scanning.According to the immune protocol;New Zealand white rabbits were immunized.The results of experimentation showed that isomerism was present in cis-and trans-forms of DES and its derivates;which was effected obviously by polar solvents.High resolution mass spectroscopy revealed that the molecular mass of DES-MCME was 325.The optimal conjugation ratios of immunogen and coating antigen were 13 and 10.The dilution rate of antiserum could reach 102400;through an indirect enzyme-linked immunosorbent assay (ELISA).The preparation method of DES-MCME was developed.The effectiveness of the artificial antigen of DES was established by high resolution mass spectroscopy and ELISA methods.This could provide the basis for the DES ELISA kit.