Congenital ureteropelvic junction obstruction (UPJO) is defined as obstruction of the ureteropelvic junction due to congenital hypoplasia, abnormal development or compression by ectopic vascular fibrous cords, resulting in obstruction of urinary drainage from the renal pelvis to the ureter, accompanied by dilatation of the renal collecting system and This is accompanied by dilatation of the renal collecting system and secondary renal damage. Dilation of the renal collecting system is not the same as the presence of obstruction. It is very difficult to accurately define the presence of obstruction, but it is generally accepted that obstruction means that urinary excretion is affected and that renal damage will occur if left untreated. Ma Honggui, Department of Urology, Affiliated Hospital of Guizhou Medical University [Etiology] There are many causes of congenital UPJO, and the exact cause is not yet clear, but can be broadly categorized into 3 types. [Diagnosis] I. History questioning Recommended items 1. Clinical manifestations of UPJO vary according to the age of diagnosis. Most children can state that they have epigastric or periumbilical pain, and older children can also state that the pain comes from the affected lumbar region. In adults, congenital UPJO is often found as a result of chronic low back pain or acute renal colic, and in some patients it is found incidentally during imaging examinations for other diseases of the abdomen or spine. 3. Some patients may have renal calculi, which may lead to renal colic and hematuria.6 The dilated renal pelvis may rupture due to external force, which may lead to acute abdomen.7 The dilated collecting system compresses the blood vessels in the kidney, which leads to renal ischemia and reflexively increases renin secretion, which may lead to hypertension.8 Bilateral hydronephrosis or unilateral hydronephrosis may lead to renal insufficiency in advanced stages. The child’s growth is slow, developmental delay, feeding difficulties or anorexia, etc. Second, ultrasound is the most common means of screening, the recommended items. Recommended items IV. Voiding cystourethrography (VCUG) Recommended items V. Intravenous urography (IVU) Optional items VI. CT angiography (CTA) Optional items VII. MR urography (MRU) and MR angiography (MRA) Optional items VIII. (Whitaker Test), percutaneous nephrostomy, retrograde ureteropelvic angiography are invasive and may induce urinary tract infection. 【Treatment】 i. Prenatal treatment ii. Non-surgical treatment iii.