The six tests of renal function mainly include creatinine, urea nitrogen, uric acid, cystatin C, β2-microglobulin, α1-microglobulin. 1. Creatinine: Creatinine is the product of muscle metabolism in the body, which is mainly excreted by the kidneys. Blood creatinine concentration mainly depends on glomerular filtration function. When the glomerular filtration function is reduced by acute or chronic glomerulonephritis, blood creatinine can be elevated. 2. Urea nitrogen: Urea nitrogen can be filtered out from the glomerulus, and is often used as a diagnostic and screening indicator of glomerular filtration function. When glomerular filtration function is reduced, urea nitrogen will increase. 3. Uric acid: Uric acid is the end product of purine metabolism, excessive increase can cause hyperuricemia, gout and other diseases. 4. Cystatin C: Cystatin C is only cleared by glomerular filtration and reabsorbed in the proximal tubule, but after reabsorption it is completely metabolized and not returned to the bloodstream, so it is an ideal endogenous marker reflecting changes in the glomerular filtration rate. 5. β2-microglobulin: it can be freely filtered from the glomerulus, absorbed in the proximal tubule, and broken down and destroyed in the epithelial cells of the renal tubule, so the excretion of β2-microglobulin is very small under normal circumstances. 6. α1-microglobulin: free α1-microglobulin in the blood can freely pass through the glomerular filtration membrane, and most of it is reabsorbed and metabolized in the renal proximal tubule, and only a small amount of it is discharged from the final urine. Its increase is common in impaired glomerular filtration function and other conditions. If the six values of renal function tests are abnormal, it is recommended to go to regular hospitals and follow the doctor’s instructions for standardized diagnosis and treatment.