Orbital meningoencephalocele is a congenital abnormality caused by the herniation of intracranial structures into the orbit through bone defects. Simple herniation of the meninges, which contains cerebrospinal fluid and forms a cystic tumor, is called meningocele, and herniation of the meninges with brain tissue is called meningoencephalocele. According to the location of the bone foramen, meningoencephalocele is divided into two clinical types: anterior and posterior. Classification by location is of great significance for diagnosis and treatment. Congenital or acquired orbital bone defects can cause the contents of the cranial cavity (meninges, brain and cerebrospinal fluid) to protrude into the orbit, causing a series of eye symptoms and signs called meningocele and meningoencephalocele.