Okadaic acid(OA)is one kind of lipophilic marine biotoxins,and main pathogenic factor of diarrheic shellfish poisoning(DSP).In this paper,the artificial antigen was made by coupling hapten of OA with keyhole limpet hemocyanin(KLH)using active ester method,and the artificial antigen was tested by SDS-polyacrylamide gel electrophoresis and IR spectrum.After being obtained from rabbits,the antiserum was purified by Chromatography on Protein A Sepharose CL-4B gel column,and the purification efficiency was verified by ultraviolet scanning and ciELISA.The results showed the artificial antigen was prepared successfully and lots of interfering substances were removed.After being purified,the concentration of antiserum was 2.16 mg/mL,it had high titer(12 800)and sensitivity(the value of IC₁₅ was 3.41 ng/mL),which was tested by ciELISA.The success of obtaining polyclonal antibody against OA with high titer and affinity provides the solid foundation which is practical and theoretical for developing rapid and economical detections.