Myelolipoma of the extra-adrenal gland is a rare,benign tumor comprising mature fat tissue and hematopoietic elements.Most myelolipomas are asymptomic and discovered incidentally.We presented a 44-year-old male who was admitted to our hospital for fight kidney dystrophy and renal calculus.Ultrasound examination of right kidneys showed hydronephrosis.Intravenous pyelography showed the right renal contour was unclear,with a circular high-density shadow inside.The nephrectomy was performed with renal myelolipoma as a final pathologic diagnosis.