A 73-year-old man with fever, lumbago and hemosputum showed ground-glass opacity around multiple lung nodules on chest computed tomography. Examination of the man revealed anemia. Specimens obtained by video-assisted thoracic surgery revealed angiosarcoma, but the primary site of angiosarcoma could not be detected before autopsy. Angiosarcoma is a rare malignant neoplasm with rapid proliferation and they can arise at any region of the body. It can originate in the skin, soft tissue, liver or heart. Their multicentric and local recurrence easily leads us to misdiagnosis, and we have struggled to reach diagnosis and its origin. Angiosarcoma should be included in the different diagnosis of diffuse pulmonary hemorrhage with multiple lung nodules.