Renal failure can be divided into acute kidney injury and chronic renal failure according to the course of the disease. Acute kidney injury may be caused by factors such as hemorrhage, and chronic renal failure may be caused by factors such as chronic nephritis. 1. Acute kidney injury: acute kidney injury may be caused by hemorrhage, congestive heart failure, acute myocardial infarction and other factors leading to pre-renal acute kidney injury; renal acute kidney injury may be caused by renal ischemia, renal toxins leading to renal parenchymal lesions; post-renal acute kidney injury is generally related to urinary tract obstruction, such as intravesical stones, prostate tumors and so on. 2. Chronic renal failure: chronic renal failure is mostly caused by chronic nephritis, diabetic nephropathy, hypertensive renal arteriolar sclerosis, polycystic kidney and other factors, and the patients will have symptoms of renal hypoperfusion, dysfunction of the body’s internal environment and other symptoms. Patients with renal failure are recommended to be admitted to the hospital for examination and timely compliance with the doctor’s instructions for standardized treatment.