A case of ectopic ureter without urinary incontinence despite its ureteral orifice in the vestibulum is reported. A 2-year-and-9-month-old female was referred to our hospital with the pain of external genitalia, pollakisuria and macroscopic hematuria. Examination revealed a complete double system of the left upper tract with vestibular opening from the upper moiety. She did not show any signs of ureteric incontinence after the establishment of voiding habits. Because radioisotope (RI) scintigram showed apparent uptake in the upper half of the left kidney we performed left ureterocystoneostomy with psoas hitch procedure. We postulate that the incontinence mechanism is maintained when the running course of the ectopic ureter is through some portion of the urethral sphincter musculature. This is the 10th case reported in Japan.