목적: The aims of this were to determine if a correlation exists between the level of hypoxia induced by severe obstructive sleep apnea syndrome (OSAS) and the level of auditory dysfunction, and that this relationship is verifiable using polysomnography (PSG). 방법:Retrospective review of 19 patients with severe OSAS resulted was performed. Independent risk factors for hearing impairment were parameters of PSG, which were analyzed in two hearing groups by a level over or equal to 40 decibel (dB). 결과:Oxygen saturation, especially the lowest oxygen saturation level, showed lower thresholds in the hearing impairment group than the control group (p = 0.039 at NREM stage, p = 0.029 at REM stage, and p = 0.002 at total sleep stage). After adjustments of other risk factors, the sole variable that remained significant was the lowest oxygen saturation (total) (p = 0.032). In the correlation analysis, a decreasing lowest oxygen saturation (from all subjects, N = 19) correlated with a greater mean hearing threshold (R2 = 0.363 and p = 0.017 on left ear R2 = 0.285 and p = 0.027 on right ear). 결론:We can see that the lowest oxygen saturation is the only variable to affect the hearing threshold. This finding could be predictive of possible hearing alternation in patients with severe OSAS.