Pulmonary adenocarcinoma complicated with a pulmonary infarction presenting as an intrapulmonary metastasis is relatively rare. We present a case of pulmonary infarction manifesting as intrapulmonary metastases of lung cancer. A previously healthy 59-year-old woman was admitted to our hospital on May 16, 2002 for evaluation of multiple abnormal radiographic shadows in the right lower lung field. Laboratory tests showed no abnormalities except for a slight elevation of carcinoembryonic antigens. Computed tomography of the chest revealed a hilar mass lesion with parenchymal lesions in the periphery of the right lower lobe, highly suspected to be a pulmonary adenocarcinoma with intrapulmonary metastases. A diagnosis of pulmonary adenocarcinoma was confirmed by a transbronchial brushing examination. A right middle and lower bilobectomy with mediastinal lymph node dissection was needed by hilum lymphadenopathy and a lower lobe invasion of the main tumor. Histopathological findings of the resected specimens revealed poorly differentiated adenocarcinoma of the lung with N1 (#11i) disease and multiple pulmonary infarctions with coagulation necrosis and recanalization. Pulmonary infarctions are demonstrated on chest x-rays as round or polygonal in shape, and located at the periphery of the same lobe as the primary tumor. Computed tomography is more sensitive than conventional radiography in the detection of pulmonary infarction. Our case suggests that pulmonary infarction associated with lung cancer should be considered as one important cause of peripheral pulmonary nodules.