Abstract: In order to investigate the influence of smoke moisture on cigarette taste,the moisture in gas phase and particulate matter of mainstream cigarette smoke of 20 domestic brand cigarette samples was trapped by a tandem impingement sampler containing the mixture of isopropyl alcohol and ethanol as an absorber,and then determined with Karl Fischer titration method.The results indicated that the limit of detection of micro moisture was 0.35 mg/mL,the recovery was over 95%,and the RSDs of the moisture content in particulate matter and gas phase were 3.5% and 4.5%,respectively.The moisture contents in particulate matter and gas phase ranged from 1.33 to 3.01 mg/cig.and from 3.71 to 8.89 mg/cig.,respectively.It was concluded that the moisture content in gas phase of mainstream smoke might be one of the important factors affecting the smoking quality of cigarette.