Urine is blood red may be food and drug factors, local injury, urinary tract infection, urinary tract stones, urinary tract tumors and other factors. 1. Food and drug factors: consume a lot of red dragon fruit or long time to take anti-tuberculosis drugs rifampicin, will lead to red urine color, no other clinical symptoms, do not need special treatment. 2. Local injury: such as strenuous exercise or foreign body stimulation, resulting in local damage to the urethra, will make the urine red, accompanied by mild pain and swelling of urination. 3. Urinary system infection: for example, acute urethritis or acute cystitis, the infection is more serious, resulting in local damage bleeding, will cause hematuria, accompanied by urinary pain, urinary frequency, urinary urgency and other symptoms. 4. Urinary stones: for example, bladder stones or ureteral stones, during urination or position change, the stones move and may cause damage to the surrounding tissues, which may cause hematuria, accompanied by pain in the lower abdomen, difficulty in urination, frequent urination and other symptoms. 5. Urinary system tumor: for example, bladder tumor, with the aggravation of the lesion, the tumor local necrosis and bleeding, it will cause painless hematuria, which may be accompanied by lower abdominal distension, difficulty in urination and other symptoms. Urine is blood red, accompanied by other obvious abnormal symptoms, may be the existence of disease factors, it is recommended to go to the hospital urology department for examination and treatment.