The normal value of blood albumin is 35-55g/L. Albumin, also called clear protein, is a small molecular weight protein produced by the liver and has a very important role in maintaining the normal nutritional status of the body and maintaining the balance of colloid osmotic pressure inside and outside the blood vessels. When albumin is reduced, the patient’s nutritional status will be poor. As the colloid osmotic pressure decreases, water inside the blood vessels can permeate outside the vessels and tissue edema occurs. In the past, due to chronic malnutrition, many people developed lower limb edema, which was caused by malnutritional hypoproteinemia. In clinical practice, many patients develop hypoproteinemia due to long-term consumption, advanced malignancy and loss of albumin from urine, etc. The most effective treatment at this time is supplemental albumin therapy, and diuretic drugs can be given to those with severe edema.