The normal value of urinary transferrin is <2.5 mg/g creatinine, which can reflect the degree of damage to the glomerular filtration membrane charge barrier much earlier and more sensitively. The amount of urinary transferrin in normal people is very low, so urinary transferrin is one of the important indicators for diagnosing early kidney damage. Usually, urinary alpha 1 microglobulin, urinary immunoglobulin and urinary albumin are also checked when urinary transferrin is examined to determine the degree of kidney damage. If urinary transferrin is elevated and urinary early damage is abnormal, urinary routine, kidney function and renal ultrasound should be checked as soon as possible and a diagnosis should be made by nephrologists.