Primary osteosarcoma of the lung is exceedingly rare. A 72-year-old man was admitted to our hospital; a primary osteosarcoma of the lung was diagnosed following computed tomography-guided needle biopsy. He died of rapidly progressing respiratory insufficiency without effective treatment seven months after the onset of symptoms. Macroscopic findings at autopsy showed typical histologic features of osteosarcoma without any bony lesion. Here we present a rare case and review the clinicopathological features of 20 previously reported cases.