Abstract: The pH value, total volatile bases, total and free nicotine, total nitrogen and reducing sugar in cut tobacco and total particulate matter and its pH value, tar, nicotine, free nicotine and moisture in cigarette smoke of 33 commercial brands and 17 samples made of single grade flue-cured tobacco were determined, the smoke impact was evaluated, and the grey incidence analysis of impact relating to the routine chemical indexes was carried out.It was found that the total nicotine in cut tobacco and mainstream smoke was a major factor influencing cigarette impact, while free nicotine was a minor factor.