Abstract: Taking sepharose 4B as carrier, cyanuric chloride as activation reagent, and Erythrina trypsin inhibitor as ligand, the method of preparation of affinity chromatography resin is described. The UV and IR spectral properties of the resin are studied. The resin is used for adsorbing r-PA. The factors influencing the adsorption and desorption are investigated. The result indicates that the procedure of preparation is simple, and the adsorption capacity is high. The highest capacity of the resin to r-PA is 8.76 mg·g^-1. The adsorbed protein on the resin can be eluted adequately and the activity of the protein has no loss. The resin can be used for the separation and purification of r-PA.