Drinking more water may make it impossible to detect occult blood in urine during examination, but in most cases it cannot really eliminate occult blood in urine. There are many reasons that can cause urinary occult blood, there are physiological and pathological reasons, if it is physiological, such as strenuous exercise, fever, etc., after the physical state of the body to improve the urinary occult blood will disappear on its own, drink more water and urinary occult blood disappearance is not directly related. Pathological urinary occult blood is more common in urinary tract infections, stones, tumors, various nephritis and so on. Drinking more water may make the urine occult blood disappear, mainly because the amount of occult blood is small and combined with drinking more water, urine dilution, but without active and effective treatment, urine occult blood can not be eliminated. Urinary occult blood patients need to consult a regular hospital nephrology or urology, improve the urine routine, urine erythrocyte morphology examination, ultrasound of the urinary tract, etc., to clarify the cause of the targeted treatment.