The most common causes of calf swelling are trauma, varicose veins of the lower limbs, cardiogenic edema, nephrogenic edema, endocrine diseases and so on. 1. Trauma: If the patient’s leg is traumatized, it is easy to cause local soft tissue damage, which leads to inflammation, local redness or swelling, usually accompanied by pain. 2. Varicose veins of the lower limbs: patients with venous valve dysfunction and blood reflux can easily cause varicose veins of the lower limbs, which can be seen in the lower limbs of the thickening of the superficial veins, and may also appear in the lower part of the lower legs of the edema. 3. Cardiogenic edema: after heart failure due to various reasons, the contractility of the heart muscle will be weakened and the diastole will be limited, usually edema appears in the low hanging parts of the body in the early stage, such as the swelling of the lower legs. 4. Nephrogenic edema: edema induced by renal disease, edema first starts from the feet, and gradually develops to the calves, and some patients also have proteinuria and hematuria. 5. Endocrine diseases: if the patient endocrine disorders will cause sodium retention, such as hyperthyroidism, diabetes, etc., are prone to endocrine disorders, calf belly swelling. Causes of calf belly swelling more reasons, if the calf continues to swell and accompanied by other symptoms, it is recommended to go to the hospital in time to identify the cause of the disease, targeted treatment.