Objective To study the effect of irradiation on reduction of the allergenicity of shrimp.Method Polyclonal antibody was prepared using shrimp allergen(Tropomysin TM) purified by SDS-PAGE and treated with irradiation at 3,5,7 and 10 kGy.The affinity of irradiated TM binding to polyclonal antibody and IgE of patient allergic to shrimp was examined by ELISA.Results It was found that shrimp allergen(TM) after treating with irradiation,the affinity of IgE of patient allergic to shrimp and mouse polyclonal antibody IgG binding to irradiated TM was dose dependently reduced.Conclusion The results indicated that antigenic properties of shrimp was changed and the allergenicity can be reduced by irradiation.