Bronchial carcinoma, usually of the non-small-cell type, is uncommon after lung transplantation and occurs predominantly in single-lung transplant ex-smoker recipients on their native lung. Bronchial carcinoma of donor origin is much rarer. We report the case of a small-cell lung carcinoma of recipient origin that occurred 12 months after a bilateral lung transplantation for cystic fibrosis in a 25-year-old woman who was a non-smoker. The tumor was of recipient origin, due to a gender mismatch between donor and recipient. This unusual observation corroborates the hypothesis of chimerism of the bronchial epithelium after lung transplantation.