For the risk assessment of airborne chemicals, a variety of in vitro direct exposure systems have been developed and applied in the biological evaluation of cigarette smoke. In direct exposure systems, cells are exposed to cigarette smoke as an aerosol at the air-liquid interface. This exposure scenario can be adapted to the situation of cigarette smoke exposure in the human respiratory system. The purpose of this study is to clarify whether the smoke exposure for the cells using the CULTEX^® RFS module, which is a recently developed direct exposure system, is consistent with the smoke retained in the human airway. For this purpose solanesol and acetaldehyde were respectively chosen as the particulate and gas/vapour phase representatives of smoke constituents, and their deposition efficiency and balance per unit area of cell culture surface of the RFS module were measured (dosimetry). We also conducted human retention studies to compare with the dosimetry data. We estimated the regional retention efficiency and balance of each representative per unit area of respiratory tract (mouth, bronchi and alveoli separately). The deposition efficiency of solanesol and acetaldehyde decreased dependent on dilution flow rate and ranged from 0.26 to 0.0076%/cm². The ratio of deposited acetaldehyde to deposited solanesol ranged from 0.96 to 1.96 in the RFS module. The retention efficiency of solanesol and acetaldehyde in the mouth and the bronchi ranged 0.095–0.0083%/cm². The lowest retention efficiency (0.0000063%/cm²) was observed in the alveoli. The ratio of retained acetaldehyde to retained solanesol ranged from 0.54 to 1.97. From these results, it was concluded that the CULTEX^® RFS module can simulate in vivo cigarette smoke exposure in terms of the exposed particulate and gas/vapour phase chemical balance. We also found that the exposure efficiency in this module could replicate the retention efficiency in the mouth and the bronchi.