Objective: To explore the clinicopathological characteristics and prognosis of lung cancer arising in the native lung after single lung transplantation for end-stage lung disease. Methods: We conducted a respective analysis of the clinical, pathological, and follow-up data of 12 recipients who developed lung cancer in the native lung after single-lung transplantation at China-Japan Friendship Hospital from September 2017 to June 2021, among a total of 247 single-lung transplantations performed during this period. Eleven were male and 1 was female, with ages ranging from 46-67 (59.25±5.75) years. Results: Of the 12 recipients, 11 had a smoking history before transplantation. The underlying diagnosis of lung diseases before transplantation included 8 cases of idiopathic pulmonary fibrosis, 3 cases of connective tissue disease-associated interstitial lung disease, and 1 case of chronic obstructive pulmonary disease. The time interval from transplantation to the development of lung cancer in the native lung was 3 to 53 months, with an average of (30.0±16.2) months. Eleven patients had elevated levels of serum tumor markers at the time of lung cancer diagnosis. CT/PET-CT showed new nodules or FDG avidity in the native lung. The histological types of lung cancer in the 12 cases included 1 case of small cell carcinoma and 11 cases of non-small cell lung cancer (7 cases of squamous cell carcinoma, 3 cases of adenocarcinoma, and 1 case of SMARCA4-deficient undifferentiated carcinoma). There were 8 cases in clinical stage Ⅳ, 1 case in stage Ⅲ, and 3 cases in stageⅠ. Three patients in stage Ⅰ and one patient in stage Ⅲ underwent surgical treatment, while patients in stage Ⅳ were treated with radiotherapy, chemotherapy, and palliative care. At the end of this study, 10 patients had died, 1 patient survived, and 1 patient was lost to follow-up. The median survival time was 7 months (ranging from 2 to 47 months), and the 1-year cumulative survival rate was 9.2%. Conclusions: The risk of developing lung cancer in the native lung after single lung transplantation is increased. The prognosis is very poor. Most of the histological types are squamous cell carcinoma. Close monitoring of high-risk populations after transplantation for early tumor detection may prolong survival time.