Hydrocephalus occurs after pituitary tumor surgery, which is not very common in neurosurgery. Hydrocephalus can be either obstructive hydrocephalus or traffic hydrocephalus. In the case of obstructive hydrocephalus, it may be the result of a hemorrhage after surgery for a pituitary tumor, which blocks the cerebrospinal fluid circulation channels, especially the third ventricle or the midbrain aqueduct. In this case, if the hydrocephalus continues to worsen and the intracranial pressure increases dramatically, external lateral ventricular drainage surgery is needed. If a more serious intracranial infection occurs after the pituitary tumor surgery, and the inflammatory material ultimately clogs the superior sagittal sinus, which has caused the traffic hydrocephalus, a lateral ventricular ventriculo-peritoneal shunt needs to be considered as the surgical treatment.