Blood in urine may be caused by cystitis, vesiculitis, kidney stones, glomerulonephritis and other diseases. 1. Cystitis: Cystitis may be caused by bacterial infection, drugs, chemical stimulation, radiation therapy and other factors. Patients will mainly appear urinary urgency, urinary pain, lower abdominal pain and other symptoms, some patients may be accompanied by hematuria. 2. Vesiculitis: Vesiculitis may be caused by infection, seminal vesicle abscess, excessive sex, cold, perineal injury and other factors. Patients may experience localized pain, frequent urination, painful urination, hematuria and other symptoms, and some patients show blood in the urine. 3. Kidney stones: Kidney stones are formed when the concentration of stone-forming substances in urine increases or the solubility decreases due to certain factors. Patients may have symptoms such as lower back and abdominal pain, hematuria, nausea, vomiting and irritability. 4. Glomerulonephritis: acute nephritis, iga nephropathy, vasculitis kidney damage, lupus nephritis, etc. can appear hematuria, targeted treatment for specific causes. There are many reasons for patients to have blood in urine, it is recommended that patients go to regular hospitals to find out the cause of the disease. Once the diagnosis is confirmed, you need to take into account your own situation and actively cooperate with the doctor to take relevant treatment measures.