The black eye is normally completely transparent, and if a black spot appears, it is mainly due to the following two reasons: First, it is caused by a foreign body in the cornea, which is usually seen in workers engaged in cutting, welding, etc., or patients who live or work in an environment with strong wind and sand. The black spots on the black eye are caused by sand or iron particles that enter the eye and embedded in the cornea, etc. There will also be eye congestion, redness, pain, photophobia, tearing, and a strong sense of foreign body. It is necessary to go to the ophthalmology department of the hospital as soon as possible, and the doctor will remove the corneal foreign body after using anesthesia eye drops to spot the eye, otherwise it will cause corneal infection. Especially iron foreign body will also form corneal rust, which will cause irreversible damage to vision. Secondly, due to iris pigmented nevus, it is not that the cornea itself appears black, its deep side of the iris has a black patch through the cornea is observed to form, it looks as if it is on the cornea.