To obtain Erysipelothrix rhusiopathiae(E. rhusiopathiae) special IgG with high specificity and purity, we use the antigen reverse adsorption combined with recombination protein A (SPA) of staphylococcus affinity chromatography to purify the specific IgG from swine serum. The result showed that the volume of serum showed little influence on the amount of IgG obtained, while the amount of bacteria was positively related to the yield of IgG E.rysipelothrix rhusiopathiae specific IgG was first purified from swine serum, and then subjected to SPA affinity chromatography, the final concentration of the IgG obtained is 240 μg/mL, thus, we get 360 μg antibody from the 8 mL swine serums, the purity of which is about 100% which can be applied in phage display.