We used derived auditory brainstem response(ABR) technique in order to investigate the change in traveling wave velocity (TWV) following altered inner pressure. In fourteen guinea pigs, TWV was measured after postural inversion in concert with hypoventilation intended to elevate intracranial pressure (ICP). Consecutive TWV measurements were conducted on the same guinea pigs with decreasing ICP induced by reverse-Trendelenberg position and hyperventilation. TWV measurements were undertaken on another eight guinea pigs after sequential elevation of perilymphatic hydrostatic pressure to the level of 20 cmH₂O, 30 cmH₂O, and 50 cmH₂O. TWV measurement demonstrated decreasing tendency after elevation of ICP with significant decrease in the frequency interval of 1000 to 2000 Hz. The velocity appears to be recovered with the reversal of position. When gradually increasing hydrostatic pressure was applied on the perilymphatic space of the cochlea, significant decreases in TWV were also noted in the frequency interval between 1000 to 2000 Hz. The results of this study suggest that increased inner ear pressure may reduce basilar membrane traveling were velocity particularly in the lower frequency area.