Kidney stone 9mm to the ureter does not necessarily come out soon, but may also be set in the urethra, leading to urinary tract obstruction. Kidney stones 9mm, which are relatively large in size, are usually difficult to expel naturally. Even if it can enter the ureter, it may be too large to scratch the ureteral mucosa or cause urinary tract obstruction, which may lead to symptoms such as difficulty in urination and pain. Failure to intervene in time may lead to urinary tract infection. In this case, attention should be paid to the early intervention with medication, surgery and other medical measures, which can prevent scratching of the urethra and formation of obstruction. For patients, it is important to seek medical treatment in time and take scientific and standardized way of treatment under the guidance of doctors.