Calf a little thicker at night, may be a normal physiological phenomenon, but also can not be ruled out is caused by cardiogenic edema, renal edema, etc., should be timely consultation to find out the cause of the disease. 1. Normal physiological phenomenon: it may be due to excessive fatigue during the day, long time standing and walking, resulting in lower leg edema, because the body will flow downward after edema, so it will cause lower limb edema. Usually it does not need treatment and can be relieved and disappear after rest. 2. Cardiogenic edema: the calf is a little thicker at night, you can do electrocardiogram, cardiac ultrasound, and plate test if necessary, to see the cardiac function. If cardiac insufficiency and edema appear, it usually indicates cardiogenic edema. It may be cardiac insufficiency or cardiac failure. 3. Nephrogenic edema: if there is protein in the urine, blood creatinine, urea nitrogen elevation, etc., it is recommended to go to the hospital in time to determine whether it is nephrogenic edema, resulting in the manifestation of the calf is a little thicker at night. Because renal insufficiency will lead to hypoproteinemia, appearing calf swelling at night. Calf a little thicker at night, there may be other reasons not arterial embolism and diabetic complications and other diseases, if exclude physiological reasons, should promptly consult a doctor to clarify the specific causes, if necessary, the appropriate treatment.