The normal value of urinary erythrocyte locus is below 80% and above 80% is abnormal. When a patient undergoes a routine urinalysis and is found to have red blood cells, more than three per high magnification field of view, it is called hematuria. Hematuria is an abnormal state, but the source of hematuria can be multi-faceted. On the one hand, it can be caused by nephritis, through glomerular filtration; on the other hand, it can also be caused by kidney stones, urinary tract infections and other diseases. It is very significant to identify these two types of causes, because the treatment and prognosis involved are different, and urine erythrocyte bitmap is often applied in the clinic for identification. Urine erythrocyte phase is mainly to observe the morphology of red blood cells, if it is hematuria caused by nephritis, the red blood cells will be deformed in the process of glomerular filtration, and the proportion of deformed red blood cells reaches more than 80%; if it is non-nephrologic hematuria, the proportion of deformities will be less than 80%. It is relatively accurate to identify renal hematuria and non-renal hematuria from this point.