There are many clinical causes of lower limb edema, and only when the cause is clearly identified can targeted treatment be carried out. The common ones are cardiogenic edema, angioedema, nephrogenic edema, and hepatogenic edema. For nephrogenic edema and cardiogenic edema, diuretics can be used to relieve edema of the lower extremities through urination. For intractable nephrogenic and cardiogenic edema, dialysis is usually required to relieve the edema of the lower extremities. For hepatogenic edema, correction of hypoproteinemia and correction of liver function can be performed to reduce edema. Patients with hypothyroidism may also develop mucinous edema of the lower extremities, which usually disappears or resolves after the hypothyroidism is cured. Filariasis can also cause severe bilateral or unilateral lower extremity edema, also known as elephantiasis. Therefore the elimination of lower extremity edema requires treatment depending on the cause.