Swollen feet at night that disappear in the morning are often seen in the normal population. This is a common physiological phenomenon and is not necessarily a pathological change. The main reason is due to the relatively large amount of activity during the day after a person wakes up, due to the work or living environment often standing or sedentary, it will cause the venous reflux of both lower limbs, blood obstruction and slowing down the return rate. A long period of time will lead to swelling in the ankles of both lower limbs, or the legs. At night when resting or sleeping, as the venous return plane of both lower extremities is basically flush with the heart, accelerating blood return, the swollen calves will gradually disappear, and the swelling will be found to be completely back to normal the next day when waking up. It is better to move both lower limbs frequently during the day to promote local blood circulation, and put the feet up 30° when sleeping at night, which is beneficial to lower limb blood return. You can also wear lower limb vein compression stockings to help reduce the swelling of the feet.