Carcinoid tumors located in the minor duodenal papilla are extremely rare, with only a few cases reported in the literature. Herein, we report the case of a 71-year-old man with a 12-mm carcinoid tumor at the minor duodenal papilla with lymph node metastases. Multidetector-row computed tomography with contrast enhancement revealed a 12-mm well-enhanced tumor in the duodenum. Upper gastrointestinal endoscopy showed a 12-mm submucosal tumor at the minor papilla of the duodenum. Biopsy specimens revealed a carcinoid tumor, and a subtotal stomach-preserving pancreatoduodenectomy was performed. Carcinoid tumors at the minor duodenal papilla have a high prevalence of nodal disease, even for tumors <2 cm in diameter. Therefore, we believe that radical resection with tumor-free margins (i.e. pancreatoduodenectomy) is the treatment of choice.