The human kidney has a very strong compensatory capacity, so there will not be any clinical symptoms in the early stage of glomerular injury, and the traditional urea nitrogen and creatinine do not change in the early stage of kidney lesions, and will only rise when the kidney function declines to the general level, and the creatinine value is more influenced by the outside world, and intense exercise will also raise creatinine, so it is impossible to achieve early diagnosis of glomerular injury, so more and more studies are conducted to find early indicators of glomerular injury. Currently, the commonly used markers of early renal injury are retinol binding protein, cystatin C, α1-microglobulin, β2-microglobulin and urinary microalbumin. Elevation of retinol-binding protein, cystatin C, α1-microglobulin and β2-microglobulin in blood indicates a decrease in glomerular filtration, while elevation of these indicators in urine indicates a decrease in renal tubular reabsorption capacity. Therefore, these four indicators are commonly used as early indicators of glomerular injury.