Choosing bio-material of Eichhornia crassipes from five plant materials through comparison on their exchangeable capacity to copper and carboxyl content, cellulose xanthogenate was prepared by raw fiber of E crassipes with NaOH and CS2. The exchange adsorption properties of the product on copper were investigated and the optimum preparing condition was obtained. The results showed that the adsorption capacity of cellulose xanthogenate of E crassipes to copper was higher than that of other plant materials. Adsorption capacity to copper ion increased with pH value increasing, and was affected by different anions, but not by sodium ion. Adsorption rate was fast and the dynamics of adsorption could be described by a first order kinetic equation. (c) 2007 Elsevier Ltd. All rights reserved.