The Authors describe the clinical presentation of a rare case of prolapsed orthotopic ureterocele in an adult. A ureterocele prolapse is relatively rare and becomes exceptional in the orthotopic ureterocele of the adult (only two cases in literature). In the case that we present, the prolapse happened in a 64-year-old woman after a cystoscopic search, that allowed the diagnosis of orthotopic ureterocele. Successive reduction was possible only after evacuative puncture, that reduced the mass and avoided strangulation and allowed non-urgent surgery correction. The therapy was a resection of the ureterocelic sac and successive reimplantation of the ureter with an antireflux technique.
