A 44-year-old woman underwent endoscopic incision of a right simple ureterocele with hydronephrosis discovered during gynecological assessment for stress urinary incontinence with Stage I cystocele. At the postoperative visits, she has reported a persistent flap of mucosa coming out from her urethra protruding in the vagina despite manual reduction. An endoscopic resection of the mucosa flap was programmed. After 24 months, she was asymptomatic with no history of renal colic or urinary tract infection. In patients with a history of pelvic organ prolapse, the resection of the ureterocele in the first instance may be the optimal choice.