Abstract: An improved method for the isolation and purification of chondroitin sulfate A (ChS-A) and chondroitin sulfate G (GhS-C) from bovine trachea was described. In order to remove combined proteihs and minimize the degradation of the mucopolysac-charides, two enzymes, trypsin and papain, were used consecutively. Subsequently, the residual proteins were removed by shaking with organic solvents, treating with adsorbent and chromatographing with ion-exchange resin. The mucopolysaccharides were further purified by precipitation with cetylpyridinium chloride and then fractionation with sodium chloride solution of different concentrations. Finally, the ChS-A and GhS-G were separated by ethanol precipitation in the presence of calcium acetate. The products GhS-A and GhS-G are very pure as proved by chemical and physicochemical analyses.