Objective: To assess and compare vestibular function in children with severe to profound hearing loss and post cochlear implant children by vHIT with normal hearing children. Patients and methods: Case control study, normal children (n=46) underwent vestibular testing (Clinical office test battery, (VEMP) vestibular evoked myogenic potential and Video Head Impulse test) and the results was compared with severe to profound sensorineural hearing loss children (n=46) and cochlear implanted children (n=43) results. All were age matched. Results: SNHL and CI children showed abnormality in office tests for Vestibulo-spinal reflex in the form of abnormal Modified CTSIB when eyes were closed. CI group showed (37%) and SNHL group showed (27%) VEMP abnormalities in one or more parameter either unilaterally or bilaterally, However vHIT results showed (47%) of abnormalities in CI group and (26%) of abnormalities in SNHL group. However, Anterior SCC VOR gain in CI group didn't affected, posterior (<0.001) and lateral semi-circular canals (<0.001) VOR gain is affected in implanted ear. Cochlear implantation, Children, Vestibular tests, Video-head-impulse test. The CI children showed VEMP abnormalities in one or more parameter either unilaterally or bilaterally our results do not show any impairment of Anterior SCC VOR function in children with CI compared to normal-hearing children. CI does not affect saccular and VOR function. There was no any correlation between VEMP, vHIT weak side and the cochlear side. The risk posed by Cochlear Implantation (CI) to the vestibular system is still under debate.