Abstract: In order to study the effects of cigarette material parameters on cigarette smoke dilution,a device for measuring cigarette smoke diffusion was established under ISO bell-shaped puff profile.Methods for measuring the dilution rate of cigarette smoke under three conditions(unlighted full length cigarette,combustion cone,burnt cigarette rods of different remaining lengths) were developed.The effects of cigarette material parameters(cigarette paper permeability,filter ventilation rate and the remaining length of burnt cigarette) on the dilution rate of cigarette smoke under the three conditions were investigated.The results showed that:1) The dilution rate of cigarette smoke under the three conditions increased with the increase of cigarette paper permeability within the range of 30-70 CU,it was 5.97%-12.16% for unlighted full length cigarette,the largest among the three conditions.2) The dilution rate of cigarette smoke at the filter end of cigarette was 0-59.81% within the filter ventilation rate of 0-50.8%,which was higher under ISO bell-shaped puff profile than under GB/T22838.15-2009 constant velocity puff profile.3) The dilution rate of cigarette smoke at the tobacco end increased with the increase of the remaining length of burnt cigarette,it was 0-12.58% while the remaining length of burnt cigarette ranged from 0 to 30 mm.