Background: Sleeve lobectomy is indicated for tumors with central localization and extension into the main bronchus or forparabronchial lymph node metastases with bronchial or mucosal infiltration. However, the risk of postoperative complicationsspecifically associated with sleeve lobectomy in lung cancer patients with obstructive pneumonia remains unknown.Case Report: The 83-year-old man who had a 59-pack-year smoking history was found to have a lesion obstructing the rightupper bronchus with complete atelectasis of the right upper lobe on chest computed tomography. In bronchoscopy, the rightupper bronchus was obstructed by mass lesion and squamous cell carcinoma was diagnosed by transbronchial biopsy at thedeep edge of the mass lesion. Fourteen days after the biopsy, the patient developed obstructive pneumonia and was hospitalized and tazobactam/piperacillin was administered. However, the pneumonia was deemed uncontrollable and urgent radical surgery for lung cancer with obstructive pneumonia was performed on the 5th day of hospitalization. Intraoperative pathological examination revealed lung cancer at the bronchial stump of the right upper lobe and right upper sleeve lobectomy with hilar–mediastinal lymph node dissection was carried out. The patient was discharged without postoperative complications 10 days after surgery. Although adjuvant chemotherapy was not administered because of his advanced age, the patient was alive without recurrence 10 months after surgery. The risk factors for sleeve lobectomy in patients with non-small cell lung cancer who develop obstructive pneumonia have not been elucidated. Accumulating additional cases will be important to clarify these risks in the future.