The process of cerebrospinal fluid production and formation in children is the same as in adults, averaging 20 ml per hour, but the clinical characteristics of their hydrocephalus differ. In children, hydrocephalus is mostly due to congenital and inflammatory lesions, whereas in adults, hydrocephalus is more common due to intracranial tumors, subarachnoid hemorrhage, and trauma. Anatomically, hydrocephalus can arise from any narrowing or obstruction in any part of the cerebrospinal fluid pathway. Physiologically, hydrocephalus is due to impaired absorption of cerebrospinal fluid. The imbalance between the formation and absorption of cerebrospinal fluid increases the cerebrospinal fluid, increases the pressure in the ventricular wall, and progressively enlarges the ventricles. The increase in intracranial pressure leads to morphological and structural changes in the brain tissue itself. In infants and young children, even though the hydrocephalus is severe and the ventricles are significantly enlarged, the fontanelle puncture pressure is still within the normal range of 20-70 mmH2O, and the change in intracranial pressure is minimal despite accommodating an abnormally high amount of cerebrospinal fluid, which is related to the unclosed cranial suture and fontanelle in infants and young children. This also suggests that changes in intracranial pressure should not be used as an indication for shunt treatment in infants and children with hydrocephalus.