The treatment of severe hydronephrosis due to kidney stones is based on the presence or absence of infection, the degree of kidney function impairment, and the patient’s age, cardiopulmonary function and other organs. Generally, if the patient’s other organs are fine, lithotripsy or stone removal can be taken to relieve the obstruction of the ureter. Stones can be treated with extracorporeal laser lithotripsy, however, due to some patients belong to the lower ureteral stones, or more obese and other reasons, can not be taken to extracorporeal laser lithotripsy, need to consider surgical removal of stones. If the patient’s situation is more critical, when the kidney stone can not be removed for the time being, it can be drained above the obstruction first, and then consider treating the stone after the infection is controlled.