Fifteen patients with stricture of upper urinary tract and 4 patients suspected of having upper tract carcinoma were managed with endourological (percutaneous or transurethral) techniques. The strictures were treated with various dilation catheters and the optical urethrotome. Eleven cases (73.3%) were successfully treated and satisfactory urinary passage was attained. The 4 patients suspected of having upper tract neoplasms were diagnosed accurately with endoscopy, 2 patients had transitional cell carcinoma of renal pelvis and the others had benign ureteral polyps. The endourological technique was a useful method for the treatment of ureteral stenosis and the diagnosis of upper tract neoplasm except for the treatment of urolithiasis. This technique will become useful tool in urology.