The eye socket is the sunken part where the eye is located. A deep eye socket will give people the feeling of deep eyes and a sense of solemnity. The main reasons for deep eye sockets are as follows: 1. Related to genetic constitution. If the patient’s orbicularis oculi muscle is congenitally thicker, or the eyelids have more pigment, the skin in this area will be darker than the neighboring parts of the skin, and the amount of pigment will show dark gray around the eyes, making the eye sockets look deeper; 2. When a patient is overly tired and does not get enough rest, the vascular blood flow is not circulating well due to autonomic dysregulation, thus causing venous blood flow blockage in the orbicularis oculi and eyelid skin. Because the color of venous blood is relatively dark, dark gray circles appear, making the eye sockets look darker; 4. Varicose veins in or around the eye sockets or eyelids may cause long-term edema of the eyelids, which can also cause venous blood to become blocked, resulting in the eye sockets looking deeper; 5. It may be related to trauma. When contusions in the eye sockets or eyelids cause subcutaneous bleeding, this can lead to dark circles or even cause sunken eye sockets, making them look as if they are deeper.