Conventional lipoma is the most common benign mesenchymal neoplasm in adults. However, bladder lipoma is a rare tumor. We report an incidental 0.5-cm, mucosal, bladder lipoma in a 75-year-old man, successfully treated with endoscopic excision. The tumor was found during the extension study of a high-grade urothelial carcinoma of the renal pelvis. A review of the published cases, including the present report, yielded a total of 16. Conclusions on this review are presented. The case is being reported because its rarity and to highlight the importance of complete workup to clarify associated disorders that may suggest extension of a malignant process.