Renal failure is a general term for renal dysfunction caused by various diseases. It is characterized by decreased renal function, metabolite retention, and imbalance of water-electrolyte and acid-base balance. In the early stage of renal failure, patients may have no obvious discomfort, only a decrease in creatinine clearance, poor urine concentration function and reduced phenol red excretion rate can be seen in the examination. Only when renal insufficiency develops to a serious stage will more obvious clinical symptoms appear. The main aspects are as follows: 1, gastrointestinal manifestations: the earliest and most obvious symptoms appear when renal failure develops to the uremic stage, which can be seen as anorexia, nausea and vomiting, abdominal discharge or constipation, and possibly gastrointestinal bleeding. 2, mental and nervous system manifestations: mental depression, fatigue, dizziness and headache, memory loss, insomnia and irritability, burning pain in the hands and feet, itchy skin, to the late stage may appear drowsiness, delirium, convulsions, coma. 3, cardiovascular system manifestations: renal failure is often accompanied by increased blood pressure, and may have myocardial damage, heart failure, as well as uremic pericarditis, pericardial effusion. 4.Hematopoietic system manifestations: Patients have anemia that cannot be easily corrected and bleed easily, such as subcutaneous petechiae, nosebleeds, gum bleeding, gastrointestinal bleeding, and even intracranial bleeding. 5.Other: Due to acidosis caused by renal failure, patients may have deep and long breathing, dry and lusterless skin, increased nocturia, dehydration due to polyuria, electrolyte disorders, acid-base balance imbalance, secondary infection, and even oliguria, edema, anuria, and other serious conditions.