Abstract: Vinyl neononanoate-chitosan(VNA-Cts) was prepared by one step free radical polymerization using VNA for hydrophobically modification of Cts, which was characterized by FT-IR and TG. Their adsorption properties for anionic dyes procion red(MX-5B) were also studied. Results showed that VNA was successfully introduced onto the Cts backbone. The maximum adsorption capacities of VNA-Cts were linearly related with the content of Cts in the relative derivative. The Cts derivative with 27.2% of grafting percentage (CtsD_27.2) was evaluated to have excellent acid resistance, thermal stability and high efficiency in removing Procion red from water and its maximum adsorption capacity was 1 180 mg/g. The data from isothermal adsorption and kinetic adsorption followed Langmuir model and pseudo-second-order kinetic model, respectively. About 80% of the adsorbed dyes could be released into NaOH solution of pH=8.