Abstract: A kind of sulfhydrylation beta- cyclodextrin- starch composite microsphere adsorbent was synthesized by inverse emulsion polymerization,using 2- thiohydracrylic acid,beta- cyclodextrin and soluble starch as raw materials. Using Fourier transform infrared spectroscopy,field emission scanning electron microscopy,X- ray diffraction and X- ray spectrometer to characterize the composite microspheres and their adsorption products,the adsorption behavior of Ag⁺was studied and the effects of different adsorption time,initial Ag⁺concentration and initial p H value on the adsorption capacity were investigated. Under the optimum conditions,the adsorption capacity on Ag⁺of the three adsorbents,which were starch microspheres,beta cyclodextrin cross- linked starch composite microspheres and sulfhydrylation composite microspheres,was studied.The results showed that the complex of 2- thiohydracrylic acid and beta- cyclodextrin was crosslinked with soluble starch,compared with composite microspheres,the crystallinity of the sulfhydrylation composite microspheres decreased,and the spherical shape was more regular.The optimal adsorption conditions of the sulfhydrylation composite microspheres to Ag⁺were as follows: the adsorption time was 40 min,the initial p H was 5,the initial concentration of Ag⁺was0.14 mol / L. Adsorption capacity was Qe( sulfhydrylation composite microspheres) > Qe( starch microspheres) >Qe( composite microspheres).