Bladder exstrophy is associated with an increased incidence of primary adenocarcinoma of the bladder. We report a rare case of squamous cell carcinoma occurring in the unreconstructed, exstrophic bladder of a 53-year-old woman treated with radical cystectomy and radiochemotherapy. This case represents the oldest patient to present with squamous cell carcinoma of an unreconstructed exstrophic bladder. We discuss the potential mechanisms of carcinogenesis in this patient, noting how they may potentially differ from those in a patient with a reconstructed bladder.