Insoluble cellulose xanthate (ICX), O-alkyl dithiocarbonate of cellulose, was synthesized and used for the removal of heavy metal ions from aqueous solutions. ICX processed carbon disulfide (CS₂) as a functional group, which was obtained by esterification of the hydroxyl group on cellulose polymer matrix with CS₂. CS₂ could form complexes with divalent transition metal ions, and the resulting ICX-metal complex was water-insoluble and settled easily. The optimum composition for ICX synthesis was cellulose/NaOH/CS₂=1 : 2 : 2.3 in mole base which showed the highest removal capacity. The selectivity and binding capacity of ICX fur heavy metals were in the order of Pb²⁺ > Cd²⁺ > Ni²⁺ and Cd²⁺ > Pb²⁺ > Ni²⁺, respectively. More than 90 % of the initial amount of heavy metals was removed within 30 min. The optimum pH was neutral or slightly alkaline, and more than 40 % of initial heavy metals was removed even in the acidic range of pH 2 to 3.