A 23-year-old man was admitted to the hospital because of acute respiratory failure accompanied by high fever and severe cough. He had started smoking about 3 weeks earlier and had gradually increased the number of cigarettes he smoked each day. After the number of cigarettes reached 10 per day, the patient experienced cough with serous sputum, high fever (38 degrees C) and dyspnea. Chest X-ray films revealed diffuse, peripheral shadows predominantly in the right lung. The patient was treated with an intravenous drip infusion of antibiotics (FMOX). On the second day of hospitalization, the dyspnea and chest X-ray shadows rapidly resolved. Although the cause of respiratory failure and diffuse shadows on chest X-ray films remained unclear, the patient was discharged. However, on the day of discharge, he smoked cigarettes and experienced cough with serous sputum for a few hours the following morning. He was readmitted for evaluation. We previously reported a case of smoking-induced acute eosinophilic pneumonia (AEP). We suspected that the present case was AEP induced by cigarette smoking but did not perform bronchoalveolar lavage or transbronchial lung biopsy for a definitive diagnosis. Although we did perform a provocation test, the patient demonstrated no respiratory symptoms without cough and respiratory failure. Blood gas analysis and pulmonary function tests also revealed no abnormalities. However, the eosinophil count (3066/mu/l) and percentage (42%) in peripheral blood increased after the patient resumed cigarette smoking, and returned to normal ranges after smoking cessation. These results pointed to a correlation between cigarette smoking and eosinophilia. This case suggested that in some patients, AEP may be induced by cigarette smoking, but does not recur after the resumption of smoking.