The experiments on 15 dogs with preformed urethral stricture or urinary urethral fistula have demonstrated that microsurgical transplantation of the vascular fasciocutaneous pedicle flap provides good functional long-term results. The best effect was achieved in cases of intraflap inclusion of previously transplanted mucosa of the urinary bladder. In all 7 experiments x-ray picture was similar to normal. Recurrent strictures or urethral fistulas were not registered. Urodynamic indices late after the experiment did not differ significantly from normal values.