Background/Aim: Nanocomposite particles are suitable for inhalation; however, their systemic migration has not been confirmed. The aim of this study was to compare drug concentrations in lungs and blood after inhalation of nanocomposite particles. Materials and Methods: Rifampicin (RFP) was used as a model drug. Nanocomposite particles were prepared from dichloromethane with RFP and poly(DLlactic acid-co-glycolic acid) (PLGA) dissolved in an amino acid aqueous solution using a spray dryer. Measurement of RFP concentrations in lung and blood of mice was performed by in vivo tests. Results: Compared with the oral administration group as a control, the RFP concentration in the lungs was significantly higher in the inhalation group. In addition, studies with a fluorescent substance suggested sustained release of drugs from nanocomposite particles in the lungs. Conclusion: Nanocomposite particles deliver pulmonary drug in an efficient and sustained manner. 543