Abstract: In order to study the effects of tobacco cut width on the particle size distribution of mainstream cigarette smoke aerosol, DMS500 fast particulate spectrometer and electrical low pressure impactor (ELPI) were used to study the particle size distribution of mainstream smoke aerosol of cigarette made of tobacco of different cut widths (0.7, 0.9 and 1.1 mm) under ISO smoking regime in terms of particle number and particle mass, respectively. The results showed that:1) The particle number presented an approximately lognormal distribution versus particle size of aerosol, and mainly distributed in the range of 40-400 nm. The particle number per cm³ smoke of cigarette with tobacco cut width of 0.7 or 0.9 mm was slightly higher than that of 1.1 mm. With the increase of cut width, count median diameters (CMD) of aerosol decreased gradually. 2) The mass of smoke aerosol mainly distributed in the range of 100-1 000 nm. With the increase of tobacco cut width, mass median diameters (MMD) of smoke aerosol decreased, the total mass of aerosol also decreased. 3) The contents of total particulate matter, tar, nicotine, moisture and CO in cigarette smoke reduced with the increase of tobacco cut width. 4) Sensory evaluation indicated that with the increase of tobacco cut width, smoke yield decreased, harshness increased, smoke shape shortened, fluffy sense increased, and the overall sensory quality of cigarette smoke deteriorated slightly. 5) As a whole, cigarette made of tobacco with width of 0.9 mm presented higher smoke particle concentration, moderate particle size, lower routine analyte deliveries, and offered better smoking quality.