Hematuria is one of the common symptoms in urology and is divided into carnal hematuria and microscopic hematuria, the latter referring to the finding of more than 3 red blood cells per high magnification field of view under light microscopy in routine urinalysis. There are many causes of hematuria, mainly the following conditions. 1, systemic diseases: including various blood diseases, nephritis, hypertensive nephropathy, cardiovascular diseases, etc. 2, urinary tumors: It is a common cause of hematuria, painless, can be recurrent, giving the phenomenon of “false self-healing”, especially to pay attention to. 3.Urological stones: Unlike urinary tumors, hematuria caused by stones is often accompanied by pain. 4, urinary tract infection: most of the symptoms of urinary frequency, urinary urgency, painful urinary tract irritation, and sometimes fever. 5, prostatic hyperplasia: in the case of difficult urination, it can be combined with hematuria, such as within 1 month after electrodesiccation, because the trauma has not been completely repaired, repeated hematuria can occur. 6, urinary tract injury: whether the injury is to the kidney or urethra, hematuria can occur. 7, other causes: for example, sports hematuria, some people also have hematuria after strenuous exercise, but it is usually lighter and can disappear on its own. Some drugs, such as sulfonamides, mannitol, cyclophosphamide, etc. can also cause hematuria.