Urine occult blood may be nephritis, but also stones, infections, etc., and may be caused by strenuous exercise, female menstruation contaminated urine. Nephritis with proteinuria, hematuria, edema, hypertension, etc. as the main manifestation, hematuria is characterized by the whole process, painless, non-coagulation; urinary tract infection so that the mucous membrane of the urinary tract inflammatory reaction, edema, bruising, destruction of small blood vessels, there may also be occult blood in the urine; stones and other reasons lead to the destruction of tissues erosion caused by bleeding, the formation of hematuria. After strenuous exercise, women’s menstrual period urine contamination, there may be occult blood in the urine, such cases are usually not serious, rest, after menstruation, pay attention to review. There are many reasons that lead to positive urinary occult blood, patients should go to the hospital in time to improve the relevant examination such as ultrasound to clarify the cause of the disease, timely treatment under the guidance of a professional doctor.