Abstract Objectives: Children diagnosed with posterior fossa tumor are susceptible to neuromuscular and musculoskeletal impairments. This study was designed to address postural stability affection in those children. Methods: Sixty children treated for posterior fossa tumor in maintenance phase aged from five to twelve years were participated in this study. Postural stability was assessed using HUMAC balance and tilt system to assess both Static and dynamic balance. Results: There was a significant difference in postural stability in children with posterior fossa tumor as compared to HUMAC balance and tilt system tests’ norms. Conclusion: From the obtained study it can be concluded that there is an affection of postural stability in children with posterior fossa tumor. Periodic evaluation along the course of treatment could identify specific impaired motor domains providing the base for a successful rehabilitation program. Keywords: Posterior fossa tumor, Medulloblastoma, HUMAC, children, Postural stability, Balance.