A 38-year-old woman was found to have a squamous cell carcinoma in a urethral diverticulum after a simple diverticulectomy. The aggressiveness of this histologic subtype of carcinoma, along with this patient's long life expectancy, supported the choice of aggressive therapy. Only nine other cases have been reported. A brief review of the published reports on the presentation, diagnosis, options for treatment, and outcomes is included.