Background:Posterior fossa tumors are the most common solid tumors found in the pediatric population. Approximately, 70–90% of patients with posterior fossa tumors present with hydrocephalus. This presents an interesting problem to pediatric neurosurgeons for which there remains no consensus: What is the best management strategy for hydrocephalus at the time of the initial presentation of the patient? Objective: This multicenter prospective cohort study compared endoscopic third ventriculostomy (ETV) and ventriculoperitoneal shunt (VPS) in the treatment of pediatric patients with secondary obstructive hydrocephalus due to posterior fossa tumors. Patients and Methods: Sixty four patients with posterior fossa tumors (24 medulloblastoma, 12 ependymoma, 27 astrocytoma and 1 schwannoma) associated with secondary hydrocephalus were divided into two equal groups according to the treatment procedure done to the secondary hydrocephalus either ETV or VP shunts, with a follow-up period of 6 months, were prospectively studied in this work. Results: Both procedures (ETV and VP shunt) proved to be effective clinically and radiographically. Endoscopic third ventriculostomy (ETV) proved to be superior due to shorter duration of surgery (17 min versus 58 min), no mortality (0% versus 6.25%), and lower incidence of procedure failure (15.6% versus 21.9%) with highest success rate of 100% was for astrocytomas followed by 80% for ependymomas and 63.6% for medulloblastomas. Conclusion: Both procedures (ETV and VP shunt) proved to be effective clinically and radiographically in the treatment of secondary obstructive hydrocephalus in pediatric patients with posterior fossa tumors. For ETV, the safety, simplicity, a more physiological of internal shunting, a significantly shorter surgery duration, absence of mortality, lower significant complications rate, a lower rate of procedure failure, the significant advantages of not becoming shunt dependent and avoidance of hardware complications (malfunction, obstruction, infection) and making safe handling and resection of the posterior fossa tumors feasible, all the previous factors made the ETV to be recommended as the first choice in the treatment of pediatric patients with obstructive hydrocephalus due to posterior fossa tumors.