Neonatal hydrocephalus is the accumulation of cerebrospinal fluid in the ventricular system or subarachnoid space due to excessive cerebrospinal fluid production or impaired circulatory absorption, and it continues to grow and increase in pressure, resulting in ventricular enlargement. The causes of hydrocephalus include: 1, congenital malformations, such as midbrain aqueduct stenosis, diaphragm formation or atresia, interventricular foramen atresia or malformation, cerebrovascular malformation, spina bifida, cerebellar subm tonsillar herniation, etc.; 2, infection, fetal intrauterine infection with various viruses, protozoa, syphilis spirochetes, etc. leading to infectious meningitis is not controlled in time, the proliferating fibrous tissue blocking the circulatory channels of cerebrospinal fluid, fetal intracranial inflammation can also make ventricular subarachnoid space or interarachnoid granular adhesions; 3, hemorrhage, intracranial hemorrhage after causing fibrous tissue hyperplasia, postpartum intracranial hemorrhage malabsorption, etc.; 4, tumors can block any part of the cerebrospinal fluid circulation, mostly seen in the fourth ventricular tumor or choroid plexus papilloma; 5, some other causes such as heredity, metabolic diseases, severe vitamin deficiencies in the perinatal and neonatal periods, etc.