Leg swelling may be caused by lower extremity varicose veins, chronic nephritis, right heart failure, hypoproteinemia and other diseases. 1. Varicose veins of the lower limbs: the occurrence of this disease is mainly related to venous hypertension and structural abnormality of the vein wall, such as congenital weakness of the vein wall, venous valve dysfunction, etc. It can be induced by factors such as low activity of the lower limbs and heavy physical labor. Most of the patients have no discomfort, and some of them will have symptoms such as lower limb soreness, edema, and fatigue. 2. Chronic nephritis: the cause of this disease is unknown, which may be related to pathogenic microbial infection, systemic lupus erythematosus, obesity, hypertension, heredity, multiple myeloma and other reasons. Early patients do not have any symptoms, with the further development of the disease, patients will have hematuria, proteinuria, edema and other symptoms, often appearing on the face, legs, hands and other places. 3. Right heart failure: the cause of the disease is related to overloading of the heart and myocardial lesions, including myocarditis, coronary heart disease, hyperthyroidism, hypertension, mitral valve insufficiency, etc. The symptoms of right heart failure include: heart failure, heart failure, heart failure, heart failure, heart failure, heart failure, heart failure, heart failure, heart failure, heart failure, heart failure, and so on. Typical symptoms of right heart failure are symmetrical depressed edema of the lower limbs, pain in the liver area, and increased nocturia. 4. Hypoproteinemia: the treatment of patients with hypoproteinemia is mainly to treat the primary disease, correct hypoproteinemia and improve the patient’s status. The causes of leg edema are many, should go to the hospital to improve the relevant examination, to clarify the specific causes of the disease.