Fighting, falls, and road traffic accidents are common causes of a black eye. A black eye can happen when something strikes a person on the face. This could be a ball, a fist, a door, or another item. A black eye can also occur after some types of dental or cosmetic surgery. The bruising can last for several days.

A black eye is caused by bleeding under the skin around the eye. Most injuries that cause a black eye aren't serious. But a black eye may indicate a more serious injury, such as an internal injury to the eye or a fracture of the thin bones around the eye.

A black eye is most commonly caused by something hitting the eye or nose. Either one or both eyes may be blackened depending on where you get hit. If you suffer a blow to the nose, both eyes may swell; the swelling is due to the buildup of fluid in the loose skin beneath the eyes.