Patients with ureteral stones can develop blood in urine, and the causes of blood in urine may be: 1. Excessive friction between stones and mucosa causes mucosal rupture and bleeding, for example, stones can cause local rupture of mucosa in the process of downstream discharge, and blood mixed in the urine can be manifested as flesh-eye hematuria, which is usually accompanied by more obvious pain, mostly due to ureteral movement and stone movement. 2. This can also cause blood in the urine, which can be accompanied by red urine, frequent urination, urgent urination, painful urination, etc. 3. These are common complications after treatment.