Abstract: To understand the filtration patterns of smoke particulate matters by cigarette filters, a pneumatic atomization device was used to generate dioctyl phthalate (DOP) aerosol with similar median diameter to that of cigarette mainstream smoke aerosol. The influences of length, pressure drop and tow specification of filter rods and puffing volume on the filtration of DOP aerosol were investigated, and a prediction model for the filtration coefficient of aerosol particles by filter rods was established and experimentally verified. The results showed that: 1) The logarithmic values of penetration rates of DOP aerosol particles showed a linear negative correlation with the lengths of the filter rods. 2) The filtration coefficients of DOP aerosol particles by cigarette filter rods were directly proportional to the pressure drops per unit length of filter rods. 3) The greater the puffing volumes, the lower the filtration efficiencies. The established predictive model for the filtration of DOP aerosol particles by cigarette filter rods accurately predicts the filtration coefficients of DOP aerosol particles at different flow rates by filter rods with different lengths and pressure drops.