Renal oncocytoma is a rare finding and represents the small percentage of all kidney tumors. This kind of tumor is benign and diagnosed accidentally (on autopsy or during nephrectomy performed for other reasons). On rare occasions, truly multiple tumors are seen, affecting the entire renal parenchyma; this condition is called oncocytosis or oncocytomatosis. Here we present two cases of this condition, diagnosed consecutively in a single internal medicine department.