We report a case in which a patient was suspected of developing pneumonia due to wearing dentures that were immersed in a storage solution contaminated with 3.0 × 108 colony-forming units (cfu)/mL of Burkholderia cepacia. It is highly possible that the contaminated denture solution entered the trachea and caused the pneumonia, possibly due to the prolonged supine positioning of the patient. We demonstrated that B. cepacia isolated from the sputum and B. cepacia isolated from the denture storage solution had the same DNA fingerprint, and that the patient recovered from pneumonia after stopping the use of dentures. These findings suggest the storage solution as the main source of infection.