Abstract:Abstract ermatan sulfate(DS),a recently known antithrOmbotic giycosaminoglycan, was isolated and purified fromdonkey skin,Physiochemical characteristics of the glycan,including constituent analysis,electrophoretic behavlour,molecular mass,speciflc lyase degradations,IR and PMR spectra were described,using porcine skin-origin der-matan sulfate as a standard reference. Contents of DS in donkey skin and its gelatinized preparations(Ejiao)werealso measured. Results indicate that the presence of DS may explain the long reputed clinical efficacy of donkey skin and Ejiao in treaing serious symptoms associated with what has been called endogenous wind in traditional Chinese medicine.