Generally speaking, mild hydronephrosis refers to the obstruction of urine drainage from the renal pelvis, resulting in an increase in intrarenal pressure, which leads to dilatation of the renal pelvis and calyces, resulting in atrophy of the renal parenchyma. If you suffer from the disease, it is recommended to go to a regular hospital as soon as possible, and you need to improve the relevant laboratory tests under the guidance of a physician to comprehensively assess the condition. It is recommended that attention should be paid to: i. Etiological treatment. Etiological treatment is the most ideal treatment, mainly to remove the cause of hydronephrosis and preserve the affected kidney. If the obstruction has not yet caused serious irreversible lesions, good results can be obtained after removing the cause. The surgical approach depends on the nature of the etiology, for example, congenital stenosis of the ureteropelvic junction can be treated with pyeloplasty. Lumpectomy for lithotripsy or stone extraction is feasible for renal ureteral calculi. These procedures can be minimally invasive surgical treatment through lumpectomy in recent years, and postoperative hydronephrosis as well as renal function will be improved. Second, nephrostomy. If the situation is critical or the cause of hydronephrosis cannot be removed in time, timely drainage should be performed at the site above the obstruction, and then the surgery to remove the cause should be performed after the infection is controlled. If the cause of the obstruction cannot be removed in time, nephrostomy is used as a permanent treatment. It should also be noted that if the hydronephrosis is too severe and the remaining renal parenchyma is too small, or if it is accompanied by severe infection, both in the case of pus accumulation in the kidney, the diseased kidney can be removed if the contralateral kidney is functioning well.