The bleeding of the navel may be caused by the following reasons: 1. It may be caused by a rupture of the local skin or mucous membrane, usually caused by trauma, such as accidentally picking the navel with the fingernails, resulting in damage to the skin and mucous membrane, resulting in bleeding. 2. It may be caused by a rash around the navel, which causes the skin to dry out and rupture, resulting in bleeding. The most common is eczema, or the formation of ringworm caused by fungal infection. 3, may be a major abdominal trauma and caused by, for example, abdominal violent impact injuries, car accidents or fall injuries, there may be local abdominal skin, or belly button skin contusions. 4, may be from the stomach inside the intestines, or other organs break through the navel skin and protrude.