Any part of the urinary system is completely or partially obstructed, acutely or chronically, due to intraluminal or extraluminal causes. If the obstruction is not removed in time, it will eventually lead to hydronephrosis and impair renal function. In the upper urinary tract, the pelvis and ureter are obstructed, and the hydronephrosis develops quickly, but often one side is damaged; in the lower urinary tract, the bladder and urethra are obstructed, and the kidney damage develops slowly at first because the bladder is used as a buffer, but often the kidney is damaged bilaterally. Urinary tract obstruction is mostly caused by mechanical reasons. However, it can also be a functional disorder. In the pediatric population, more attention should be paid to congenital lesions. In adults, stones, tumors, injuries, tuberculosis, etc. are common. In elderly men, the most common obstruction is prostatic hyperplasia. In women most are associated with intrapelvic lesions. Neurogenic bladder – nerve injury due to congenital bulging of the meninges, acquired trauma, effects of drugs, bladder stones, tumors in the bladder neck, ureteral bulge, obstruction by blood clots in the bladder, contracture of the bladder neck, etc. Compression of the ureter by retroperitoneal or pelvic masses and infiltration of cervical cancer into the posterior wall of the bladder can cause obstruction at the site of unilateral or bilateral ureteral entry into the bladder. The clinical manifestation of lower urinary tract obstruction is mainly progressive difficulty in urination, which is characterized by small urine line, weakness in urination, dripping, dripping, segmental urination, and then urinary retention and filling incontinence. Long-term lower urinary tract obstruction may also lead to hydronephrosis and renal insufficiency on both sides.