Abstract: The grafting copolymerisation(chitosan-g-DMAE-BC) of methacryloxylethyl benayl dimethyl ammonium chloride with chitosan was investigated.The antibacterial activity of it was examined against a variety of test microorganism by quantitative suspension method.The obtained polymer was inhibitory to the growth of Gram negative bacteria(Escherichia coli) and Gram positive bacteria(Staphylococcus aureus) as well as the fungus(Candida albicans).The inhibitory ratio to each of them is 99.70%,88.4%,99.21%,respectivel...