The unbearable pain of kidney stone is mainly due to the damage of ureteral mucosa caused by the process of stone discharge from top to bottom in the urinary tract, which triggers ureteral spasm. The main cause of renal colic is ureteral spasm. At present, there is no specific pain classification of mild, moderate and severe in clinical renal colic, which is related to the subjective feeling of patients, for example, some patients are more sensitive to pain and can feel more intense pain, while elderly people are less sensitive to pain and the pain sensation in the back will be lighter.