Albumin, or serum protein, is used to maintain colloid osmotic pressure, transport metabolic substances in the body, and supply nutrients. Albumin is an important protein in normal human serum and is synthesized in the liver, with an adult albumin content of about 40-55 g/L. The role of this substance is to maintain the colloid osmotic pressure of the blood, the transport of metabolic substances in the body, and the supply of nutrients. When albumin is elevated, it may be due to severe dehydration, shock and other causes of blood concentration; when albumin is lowered, it may be due to damage to the synthesizing site, i.e., the liver. Common diseases include cirrhosis of the liver, hepatocellular carcinoma, etc. Other diseases include malnutrition caused by insufficient intake of protein, and loss of protein resulting in a decrease in colloid osmolality, which may lead to oedema. If abnormal albumin is found, it is recommended to go to a regular hospital to avoid delaying the condition.