The existing forms of adsorbed Cr and the effect of PH value and Cr（Ⅵ） concentration on the forms were studied using sequential extraction and isotopic tracer technique. It was shown that the order of Cr adsorbed in different phases was Fe/Mn oxide>organic

and carbonate>residual>exchangeable. Adsorption of Cr in sediment was controlled by Cr（Ⅵ） concentration and pH value

but the distribution of Cr adsorbed in various phases was independent of these factors.Fe/Mn oxide and organic matter were the main adsorbent of Cr in sediment.