Surgery for hydronephrosis is mainly performed through three ways: patency of urine drainage, protection of renal function, and treatment of primary disease. Surgical methods include ureteral stent implantation, resection and reanastomosis of ureteral stenosis segment, indwelling urinary catheter and percutaneous nephrolithotomy. 1. Remove the primary disease, such as stones, tumors, congenital malformations and other causes of hydronephrosis, usually the surgical treatment of the primary disease first, to relieve hydronephrosis, and then hydronephrosis surgical treatment. 2. For patients with mild hydronephrosis and good renal function, ureteral stent implantation or endoscopic ureterotomy or ureteral stenosis resection and reanastomosis can be performed. For patients with hydronephrosis who have a clear etiology but cannot tolerate surgery because of their poor status, ureteral catheterization is feasible, i.e., internal drainage, which drains urine from the kidneys to the bladder, and then discharges it out of the body through the vesicourethra; or percutaneous nephrolithotomy, which directly drains urine out of the patient’s body. Patients with hydronephrosis need to consult a doctor in time to clarify the cause of the disease, to prevent further damage to kidney function, and to be treated under the guidance of a doctor.