Abstract: For better monitoring the airtightness of cigarette packets, the airtightness of cigarette packets of all brands and specifications produced by Yuxi Cigarette Factory was generally investigated by an airtightness tester aided by a set of specially designed measuring fixtures. The test results were analyzed with variance analysis and Tukey comparison. The results showed that:1) The airtightness of cigarette packets differed significantly between brands and specifications, the packets could be classified into four categories by their airtightness: < 1.0 kPa(Category Ⅳ), 1.0 to 2.0 kPa(Category Ⅲ), 2.0 to 3.0 kPa(Category Ⅱ)and > 3.0 kPa (Category Ⅰ). 2)Airtightness of cigarette packet depended on its packing format, the quality control limits determined via probability analysis were 0.30 and 1.00 kPa for soft and hard packets, respectively. 3) The barrier property of film was the main factor influencing the airtightness of cigarette packets. The quality control limit setting was validated via leakage point experiments, and a standard for the airtightness of cigarette packets was established.