A 26-year-old man was admitted to our hospital complaining of exertional dyspnea. Chest x-ray films disclosed reticulonodular shadows predominantly in the upper fields of both lungs, but no apical cap. Lung biopsy specimens obtained from the upper lobe by video-assisted thoracoscopy revealed subpleural elasto-fibrosis. Also, specimens obtained from the lower lobes disclosed micro-honeycombing due to peri-lobular fibrosis resembling usual interstitial pneumonia. Although pneumothorax occurred repeatedly, the lungs reinflated on each occasion without artificial intervention. Similar radiographic findings had been obtained on the patient's father, who died of idiopathic pulmonary fibrosis at the age of 56. Idiopathic pulmonary upper lobe fibrosis was conclusively diagnosed because the patient exhibited most of the features originally described by Amitani et al.