The isolation and purification of polysaccharide from flagelliforme by radial flow chromatography were studied. The column (7.7 cm of bed length and $229.6;cm^3$ of bed volume) was packed with DEAE-01 anion ion-exchange resin and gradient eluted with NaCl solutions. The content of the polysaccharide was determined with the phenol-sulfuric acid method. The effects of sampling weight, elution velocity, and elution concentration gradient on the separation efficiency were examined and three isolated peaks were obtained. The optimal separation conditions are 10 mg of the sampling weight (sampling volume is 20 mL), 1.0 mL/min of the elution velocity, and 1.00 mol/$L^2$ of NaCl gradient elution. The adjacent peak resolutions among the three main components (1, 2, and 3 according to their elution order) are 0.660 ($R_{12}$) and 0.786 ($R_{23}$), respectively. It is deduced that 39.8 cm of the bed length is required for the fully separation of the three polysaccharides.