Congenital stricture of the mid-ureter or lower one third of the ureter is extremely rare. Five children with this type of ureteral stricture were treated during the past 17 years. In these five children, two presented with abdominal tumor, one with hydronephrosis on prenatal ultrasonography, and one with growth retardation due to renalfailure. In one boy, the disorder was detected through the preoperative X-ray examination for hypospadias. In addition to routine IVP and voiding cystourethrography, all children had retrograde pyelography prior to or at the time of their operation. In two cases, the stricture was found at the middle ureter, and in three cases at the lower one third of the ureter. Three children had contralateral abnomalities; two with multicystic kidney and one with PUJ stenosis. In the selection of operative procedure it depends on whether or not the lower ureter distal to the stricture has normal ureteral movement. In two of cases, normal peristalsis of the distal ureter was demonstrated on IVP, and in one on antegrade pyelography under fluoroscopy. In two cases, intraoperative pressure-flow-study revealed normal intraluminal pressure of the distal ureter. End-to-end ureteral anastomosis with resection of the stricture lesion was made in all children. On Postoperative IVP their hydronephrosis and hydroureter improved in all cases.