Abstract: The experiments on application of chitosan in cigarette filter were conducted in order to reduce the risk of smoking.The chitosan-containing filter rod was made by using the mixture of triacetin and chitosan as plasticizer during the forming of cellulose acetate filter rod, and then assembled with tobacco rod.The test results showed that the free radicals in smoke of chitosan-containing filter cigarette were reduced by 3.0%-26.6% compared with control cigarette, and the smoking quality was better to a certain extent.