Urine occult blood trace mainly refers to the presence of a small number of red blood cells in the urine and a weakly positive reaction to the urinary occult blood test when performing a routine urinalysis. A weakly positive urinary occult blood does not necessarily mean that the examiner has hematuria. Usually, if the amount of red blood cells in the urine of the examiner is more than 3/HP, it may suggest the existence of hematuria, which can be divided into physiological and pathological causes. 1. Physiological reasons: more common in strenuous exercise, female menstruation, menstrual blood mixed into the urine, there will be a positive urinary occult blood, after resting can return to normal. 2. Pathological causes: can be seen in urinary tract infections, urinary stones, glomerulonephritis, urinary tract tumors, etc., in addition to systemic coagulation dysfunction can also lead to occult blood in the urine, need to be directed by a doctor according to the cause of targeted treatment, such as antibiotics (levofloxacin, etc.). If the urine occult blood weak positive situation, timely hospital consultation, clear complete urine routine, renal function, urinary ultrasound, urine erythrocyte phase difference morphology and other related examinations, clear cause of the doctor’s guidance, symptomatic treatment, to avoid delaying the condition.