The crude polysaccharide was extracted from sour jujube fruits using hot water extraction followed by ethanol precipitation.The content of crude polysaccharide was (92.6±4.72) mg/g by phenol-sulfuric acid assay, and selenium content of the polysaccharide was (17.8±2.05) μg/kg by fluorescence spectrophotometry method. After further purified by DEAE—52 and Sephadex G—75 column chromatography, a white and flocculent polysaccharide was obtained. After hydrolysis with 2M trifluoroacetic acid, TLC plates was detected and high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) was further analyzed. A comparative study of the two methods showed that the polysaccharide was composed of rhamnose, xylose, arabinose, glucose and galactose with a ratio of 3.21∶8.36∶5.63∶0.96∶1.82. The selenium polysaccharide exhibited typical absorption of polysaccharide characterized by Infrared spectroscopy (IR) spectroscopy;1H NMR and 3C NMR analysis indicated that the structure of selenium polysaccharide was pyranoid glucan withβ-glycosidic bond.