There are many causes of ankle swelling, as follows: 1, local trauma: it can cause redness, swelling, heat and pain in the ankle; 2, metabolic diseases and chronic diseases: swelling of the ankle can occur, the most common is kidney lesions, such as glomerulonephritis, chronic renal failure, hypoproteinemia, etc. can cause ankle edema; 3, hypertension: swelling of the ankle can occur, it usually develops in the morning, and patients need to measure blood pressure It is necessary to measure blood pressure and check kidney function at the same time; 4, endocrine system diseases: for example, hypothyroidism patients, due to the deposition of mucus protein in the subcutaneous tissue, can cause local edema, but this edema is different from the ordinary edema, the skin edema in hypothyroidism is manifested as the skin surface is bright and there is no depression feeling when pressed, the usual low protein edema has depressed edema when pressed; 5, diabetes mellitus: the long history of diabetes mellitus causes Diabetic peripheral neuropathy and diabetic nephropathy can cause swelling of both lower limbs; 6. Coronary atherosclerotic heart disease: heart failure can cause swelling of both lower limbs and ankle joints.