Three cases of girls, aged three, four and five years, with a single unilateral ectopic ureter draining into the vagina are discussed. All of the children had urinary incontinence. Vaginoscopy demonstrated different findings of the ectopic ureteral orifice within the vaginal mucosal fold in each child. Of the three patients, two underwent nephroureterectomy and one underwent ureteral reimplantation. Complete cure of urinary incontinence was obtained in all three children after surgery.