The process parameters of deproteinized of Sargassum Horneris extraction through radial flow chromatography was studied.Sample concentration,sample volume,sample flow-rate and elution flow-rate were studied on the influence of the deproteinization rate and polysaccharide recovery rate.The result showed that in the condition of sample flow-rate 5mL/min,the elution flow-rate 40mL/min,the sample volume 100mL and the sample concentration 5mg/mL,the deproteinization rate was 74.35% and the polysaccharide recovery rate was 80.75%.Furthermore,ultrafiltration was applied to separate the polysaccharides of passed and residues of the radial flow chromatography into three groups: less than 10ku,between 10ku and 100ku and above 100ku.The comparison of protein removal rates from polysaccharides indicated that ultrafiltration coupled radial flow chromatography improved the protein removal rates to 96%.The moisture retention capacity of polysaccharides of Sargassum Horneri indicated that the ability of preventing desorption and moisture was both improved.