Swelling of legs and feet has more causes which may be related to hypoalbuminemia, lower extremity venous thrombosis, heart failure, and so on. 1. Hypoalbuminemia: it can lead to the decrease of colloid osmotic pressure in the blood, so that the water from the lumen of the blood vessel enters the tissue interstitial space, and is deposited in the periphery, which results in the symptom of swollen legs and feet. 2. Lower extremity venous thrombosis: If lower extremity venous thrombosis occurs, venous blood flow is obstructed and venous blood is deposited in the tissue interstitial space, which can also cause leg and foot edema. 3. Heart failure: Especially in the case of right heart failure, venous return in the body circulation is obstructed, and the patient’s venous pressure rises, leading to the deposition of venous blood in the interstitial space of the tissues, which causes swelling of the legs and feet. Swollen legs and feet are also common in late pregnancy, long-term sedentary and other causes, it is recommended to consult a doctor in a timely manner, follow the doctor’s instructions for further examination, with the help of the doctor to clarify the cause, and targeted treatment or therapy.