The chitosan solution was prepared by dissolving chitosan powder into acetic acid and various organic acid solution. The average molecular weight and the degree of deacetylation of the chitosan were determined to be 50,000 and 90%, respectively. The chitosan solution was casted a certain thickness on glass, so that made membrane, respectively. And then cross-linking of the membrane with glutaric dialdehyde which was cross-linking agent. This work absorbed a harmful heavy metal in waste water using the chitosan membrane and property of permeate flux were determined. Absorbed heavy metal on chitosan was confirmed by FT-IR and analysis of sample concentration used ICP.