A 58-year-old man diagnosed with an abdominal aortic aneurysm and left renal tumor on screening ultrasonography was found in computed tomography (CT) to have an infrarenal aortic aneurysm 4.0cm in diameter and a solid mass of the lower pole of the left kidney 2.5cm in diameter, suggesting renal cell carcinoma. Simultaneous partial nephrectomy and repair of the abdominal aortic aneurysm were done via retroperitoneal approach through a left pararectal incision. The postoperative course was uneventful and no graft infection occurred. A combined approach to abdominal aortic aneurysm and renal neoplasm is still controversial in poor-risk patients, but in good-risk patients, simultaneous operativ therapy is safe and appropriate without evidence of increased mortality or morbidity.