The normal value of plasma albumin is 35-55 g/L. A decrease in plasma albumin is usually below 35 g/L, and a severe decrease in plasma albumin is below 25 g/L. When plasma albumin is severely reduced, the patient’s plasma colloid osmotic pressure decreases significantly and the patient develops edema in the limbs and, in severe cases, peritoneal and pleural effusions. Plasma albumin plays a leading role in maintaining the body’s colloid osmotic pressure because of its small molecular weight but high density, which enhances the adsorption of water. In addition, plasma albumin plays a very important role in maintaining the nutritional status of the body. In the past, many people developed hypoproteinemia due to malnutrition, which led to limb edema. Patients with reduced albumin can also be seen clinically, commonly due to chronic wasting and associated with renal loss, and generally require supplemental albumin therapy.