The anatomy of the human urinary system reveals the presence of three narrowing sites in the ureter. Due to the relative narrowness of the lumen, the stone is easy to stay here. Specific locations are as follows: 1, the renal pelvis and ureter connection, that is, the renal pelvic ureter migration; 2, the ureter across the iliac blood vessels position; 3, the ureter and bladder junction, that is, the ureter bladder migration. Stones embedded in the ureteral stenosis, such as stay longer, easy to cause ureteral mucosal edema, as well as polyp formation. Minimally invasive surgical treatment is recommended, such as ureteroscopic lithotripsy, percutaneous nephrolithotripsy and other minimally invasive procedures.