Glomerular filtration rate is an important indicator, which is the main indicator to evaluate the kidney function. The main reasons for the decrease in glomerular filtration rate are: acute kidney injury, chronic renal failure, or long-term chronic kidney disease combined with acute kidney injury on the basis of whether the decrease in glomerular filtration rate can be recovered as follows: 1, acute kidney injury: if through timely and effective treatment, kidney function can be completely recovered or partially recovered, such as acute glomerular necrosis, acute interstitial nephritis, etc.; 2, chronic acute kidney injury combined with kidney disease: can be partially recovered; 3, chronic kidney disease: the decline in glomerular filtration rate is irreversible, so it is not recoverable, but clinically it can be effectively managed to delay the rapid decline in kidney function and protect the residual kidney function of the patient’s kidneys, so that they do not enter or enter the end stage, i.e., uremic phase, as late as possible. There are more specific ways to delay the progression of chronic kidney disease, for example, by treating the primary disease, actively controlling proteinuria and blood pressure, and appropriately applying sartans to protect the residual kidney function. In conclusion, whether the glomerular filtration rate can be restored cannot be generalized; patients in the acute stage can recover completely and partially, while patients in the chronic stage cannot recover, but their progression can be delayed by other means.