Carcinoma of the ampulla of Vater associated with annular pancreas is a rare entity. Only seven cases have been reported so far in the English literature. We herein report one such case in a 42-year-lady who presented with progressively increasing jaundice and pain in the upper abdomen for past 2 months. A magnetic resonance cholangiopancreaticography (MRCP) and MRI revealed an annular pancreas with an ampullary mass and a dilated CBD. An upper gastrointestinal endoscopic biopsy from the ampullary mass revealed a moderately differentiated adenocarcinoma. She was diagnosed as having annular pancreas with periampullary cancer that was subsequently confirmed at laparotomy. Histological examination confirmed a complete annular pancreas with a 2 cm × 2 cm moderately differentiated adenocarcinoma of the ampulla of Vater. The management, however, remains as in any case of periampullary malignancy. This highlights the importance that obstructive jaundice in an adult patient presenting with annular pancreas may be associated with a coexisting periampullary malignancy.