The blood vessels on the back of the feet are very visible which may be normal or pathological. Normal phenomenon is seen when the skin is white and the body is thin, the blood vessels in the feet, especially the veins, are very obvious. In pathological cases, it can be caused by stagnation of venous blood due to poor venous blood return, venous valve insufficiency, venous thrombosis, etc. In this case, it is necessary to actively do cardiac ultrasound and vascular ultrasound to clarify the diagnosis, and then do the next step after the diagnosis is clear.