We studied 10 lung cancer patients with pneumonia insusceptible of conservative treatment. All patients underwent urgent pulmonary resection to control their pneumonia induced by the tumor and to cure the cancer. The causes of pneumonia were bronchial obstruction by the tumor itself or aspiration of the tumor necrosis. The patients comprised 9 men and 1 women. The age range was 37 to 72 years with a median age of 57 years. There were obstructive pneumonia in 3 patients and aspiration pneumonia in 7 cases. The average size of tumor was about 4.7 and 7.5 cm, respectively. The histological type of lung cancer was squamous cell carcinoma in 6 and adenocarcinoma in 4. There were 1 stage 1,1 stage IIIA and 3 stage IIIB tumors. Lobectomy was performed in 8 patients and pneumonectomy in 2 patients. Nine patients underwent the operation under one-lung ventilation. A median period of preoperative administration of antibiotics was 6.2 days. The curative operation for lung cancer was performed in 3 patients and non-curative operation in 7 patients. Postoperative complications were pneumonia in 2, subcutaneous abscess in 2 and arrhythmia in a case of pneumonectomy. All non-curative patients died in 5 years, but two curative patients survived long time for 31 and 75 months, respectively. We performed urgent pulmonary resection for lung cancer patients to cure fatal pneumonia and cancer. There were no hospital death. Urgent pulmonary resection could prevent early death caused by fatal pneumonia by tumor itself.