Abstract:Three polysaccharides AC-A, AC-B, AC-C were isolated and purified from the water extract of the root of Cynanchum auriculatum. The molecular weight of AC-A, AC-B and AC-C were 28000, 51000 and 117000 respectively. All these polysaceharides were composed of rhamnose, arabinose, xylose, galactose, mannose and glucose.