Benign tumours and primary malignant tumours of the ureter are uncommon in adults and extremely rare in children. The clinical symptoms are flank pain, urinary tract infection, and macro/micro-haematuria. There is an incomplete ureteral obstruction and filling defect on intravenous urography (IVU). Optimum treatment of this lesion results in renal preservation. Uretero-renoscopy is currently the best method available for the identification and histological diagnosis of ureteral polyps. Recommended operative procedures are pyeloureteric junction (PUJ) resection with Anderson-Hynes pyeloplasty, ureteric resection with end-to-end anastomosis or with uretero-cysto-neoanastomosis (UCNA), ureteric resection with renal autotransplantation. Ureteronephrectomy is not indicated. A case of ureteral polyps in a 17-year-old boy with the chief complaint of left flank pain is reported here. The excretory urogram and renal scan showed left hydronephrosis. Resection of the pyeloureteral junction, partial resection of the upper ureter containing the lesions--multiple branching 30-40 mm long polyps with a common basis--and Anderson-Hynes pyeloplasty were performed. The pathological diagnosis was benign fibroepithelial polyps of the ureter. Convalescence was uneventful and after 4 years of follow-up, excretory urogram and ultrasonography showed good renal function and improvement of hydronephrosis.