Abstract: To characterize the composition of post-nasal exhaled aerosols (PEAs) in smokers, an analytical method based on large-volume thermal injection-in-column evaporation concentration was developed. Utilizing a newly designed PEA collection device and optimized parameters, the aerosol components exhaled by smokers of flue-cured and blended cigarettes were analyzed. Concurrently, a smoking machine was employed to simulate actual human puffing profiles to quantify the release levels of inhaled aerosols, which were then compared with the PEA components. The results showed that: 1) A total of 158 chemical components were detected in the PEAs, with relative standard deviations (RSDs) all below 15%, and 100 of these components exhibited RSDs below 10%. 2) For both flue-cured and blended cigarettes, the release levels of aerosol components in retro-haling PEAs were significantly lower than those in inhalation PEAs. While the average retention rates across different chemical categories showed minimal variation during inhalation, significant disparities were observed among categories during retro-haling. 3) During the consumption of both cigarette types, inter-individual variations in aerosol retention rates were relatively small. In contrast, differences in retention rates driven by specific smoking behaviors were more pronounced.