Abstract: Because polysaccharides from Ephedra sinica stem have reported to possess important immunosuppressive activity,it is significant to identify and discriminate polysaccharides from several kinds of legal base source of Genus Ephedra.This study realized the discrimination of polysaccharides from Ephedra sinica Stapf, E.intermdia Schrenk et C.A.Mey., E.equisetina Bge and Badix Ephedra employing UPLC-MS/MS techniques based on changeable rules of compositional monosaccharides by full acid hydrolysis.The results showed 20 batches of Ephedra polysaccharides was successfully discriminated using UPLC-MS/MS coupled with multivariate statistics method,such as principal component analysis (PCA).These Ephedra polysaccharides were attributed to different species and plant parts.Man (1),GlcN (2),GalUA (8) and Glc (9) played an important role in classifying between E.sinica polysaccharides and polysaccharides from E.intermdia、E.equisetina and Badix Ephedra,while Gal (10) played an important role in classifying between E.equisetina polysaccharides and polysaccharides from E.intermdia,E.sinica and Badix Ephedra. This method with the advantages of high stability and repeatability,could achieve a quality evaluation of plant polysaccharides from three kinds of legal base source of Genus Ephedra.

Key words: Ephedra polysaccharides, full acid hydrolysis, compositional saccharides, UPLC-MS/MS;PCA