Facial edema may be associated with kidney disease, liver disease, heart disease, severe anemia, and allergies. 1. Facial edema caused by kidney disease is related to sodium retention caused by decreased glomerular filtration and increased tubular reabsorption of sodium and water. 2. Facial edema caused by liver disease is usually related to hypoproteinemia caused by prolonged illness, which is mainly seen in patients with liver cirrhosis or liver cancer. 3. Facial edema caused by heart disease is related to the obstruction of blood flow due to heart failure. 4. Facial edema caused by severe anemia is associated with hypoproteinemia. 4. Facial swelling caused by skin allergies, also known as allergic reactions, is associated with localized inflammatory stimuli and vasodilatation. Facial swelling can be caused by a variety of reasons, the specific situation requires a doctor’s visit and complete the relevant examination.