Abstract: The fucoidan complex(HSP0)was prepared by ultrasonic assisted hot water extraction from Sargassum henslowianum,and the crude polysaccharide(HSP1)was obtained by deproteinizing HSP0. The HSP1 was purified by DEAE-52 cellulose anion exchange chromatography to obtain F1,F2 and F3.The chemical composition analysis of five fucoidans of HSP0,HSP1,F1,F2 and F3 were carried out,and the monosaccharide composition analysis of HSP0 and F2 were carried out. Furfural colorimetric method was used to study the ability of different concentrations of HSP0 to bind bile salts in vitro and to compare the ability of five fucoidans to bind bile salts in vitro. The results showed that among the five components,HSP0 had the highest polysaccharide content,reaching 37.87%,F3 had the highest sulfate group content,reaching 18.56%,and F2 had the highest fucoidan content,reaching 17.64%. Monosaccharide composition analysis showed that the percentage of fucose and galactose on the F2 sugar chain were 16.17% and 16.13% higher than HSP0,respectively. The ability of HSP0 to bind bile salt increased with increasing of concentration,and approached saturation after 10 mg/mL. When the concentration of five fucoidans were 2 mg/mL,F2 and F3 had the best ability to bind cholate. F2 had the strongest ability to adsorb sodium taurocholate,the adsorption rate reached 13.36%;F3 had the strongest ability to adsorb sodium cholate and sodium glycinate,with adsorption rates of 26.35% and 11.35%.