In March 1995, a 54-year-old woman was admitted to a hospital because of exertional dyspnea and her condition was diagnosed as primary pulmonary hypertension. In September 1996, respiratory difficulty and hemosputum were woted. The chest computed tomographic scan showed diffuse micronodular opacities, and she was admitted to our hospital for examination of other pulmonary conditions giving rise to pulmonary hypertention. However no lung biopsy could be performed, because the pulmonary arterial pressure was too high. Although the patient received medication, she died of progressive right heart failure. The pathological diagnosis at autopsy was pulmonary capillary hemangiomatosis (PCH). Although PCH is a very rare disease that causes secondary pulmonary hypertension, it is important to distinguish it from primary pulmonary hypertension and pulmonary veno-occlusive disease.