A 48-year-old man was admitted with hemoptysis, malaise, fatigue and anorexia in the last twenty days. A centrally located, 3 cm soft tissue mass in the right lower lobe of the lung was discovered on radiologic evaluation. His clinical and laboratory evaluation was unrevealing. Bronchoscopy, bronchial cultures and brushing were all negative. He underwent right thoracotomy with the radiologic suspicion of lung cancer. The frozen section was implying malignancy and the patient underwent a right lower lobectomy with mediastinal lymph node dissection. However, the routine histologic report showed bronchiolitis obliterans organizing pneumonia. Corticosteroids were not given and there is no clinical or roentgenographic evidence of recurrence of the disease twelve months postoperatively. This interesting case demonstrates that not only clinical or roentgenographic findings of bronchiolitis obliterans organizing pneumonia but frozen section too, can be confused with those of lung cancer.