Swollen ankles without pain may be due to poor blood circulation, cardiogenic edema, nephrogenic edema and other conditions. 1. Poor blood circulation: when patients stand for a long time, sit for a long time, due to poor venous return of blood, it can lead to edema in the ankle and other low hanging parts of the body, which may not be accompanied by pain. 2. Cardiogenic edema: if the patient has basic heart diseases, cardiac insufficiency can lead to edema in the ankles and other parts of the body, but not accompanied by pain and other discomforts. 3. Nephrogenic edema: Kidney diseases such as nephrotic syndrome can lead to a decrease in the glomerular filtration rate, resulting in the accumulation of water in the body, which can cause swelling of the ankles and other parts of the body, usually without other discomforts. Swollen ankles without pain can be caused by a variety of reasons, it is recommended to go to the hospital in a timely manner, improve the relevant examination for active treatment.