In order to study the effect of circumference and filter ventilation rate on the release of alkaline flavor components in cigarette mainstream smoke, CH2Cl2 extraction and GC/MS analysis were used to measure the mainstream smoke of cigarette samples with different circumference and filter ventilation. The release amount of 21 kinds of basic flavor components in tobacco. The results showed that: The various basic flavor components and the total amount of basic flavor components released per gram of shredded tobacco showed an increasing trend with the increase of the circumference of the cigarette. The increase of ventilation showed a decreasing trend; Analysis of variance results showed that the release of pyridine, pyrazine and quinoline aroma components and the total amount of alkaline aroma components were significantly different among different filter ventilation rates. Level, the release of pyrazines and quinolines among different circles reached a very significant difference; increasing the same filter ventilation, the release of pyrazines and quinolines decreased the most, followed by pyridines and quinolines. phenotype aroma components.