The severity of the disease cannot be judged solely on the basis of the degree of elevation of one indicator of β2-microglobulin, but needs to be analyzed in combination with other related tests, such as kidney function, urine protein quantification and other comprehensive analysis. Beta 2 microglobulin is divided into blood beta 2 microglobulin and urine beta 2 microglobulin. Elevated blood β2-microglobulin is commonly found in chronic renal insufficiency, malignant tumors and other diseases, while elevated urinary β2-microglobulin is commonly found in renal tubular injury and various nephritis. Elevated blood β2 microglobulin combined with elevated creatinine, uric acid and other considerations of chronic renal insufficiency, at this time, blood β2 microglobulin index does not represent the degree of decline in renal function, and need to be judged according to the glomerular filtration rate. Elevated β2 microglobulin combined with elevated NAG enzyme, α1 microglobulin, retinol-binding protein consider renal tubular injury, and if the urine protein is generally elevated consider various nephritis. If all the indicators are normal, only β2 microglobulin is slightly elevated, it may be normal fluctuation, usually not serious, and it is recommended to review again after rest.