Abstract: Objective To observe the alterations of auditory brainstem response(ABR) in guinea pigs with gentamicin-induced hearing loss under awake and anesthetic conditions.Methods We recorded the ABR in 20 normal guinea pigs and 20 with gentamicin-induced hearing loss before and after anesthesia for statistical analysis.Results No significant difference was observed in the waveform,response threshold(RT),Ⅰand Ⅲ peak latencies(PL),Ⅰ-Ⅲ interpeak latencies(IPL) of ABR between awake and anesthetic conditions in normal guinea pigs(P>0.05),nor did gentamicin-induced hearing loss showed obvious impact on the ABR parameters(P>0.05).Conclusion No significant ABR alterations occur under awake and anesthetic conditions in either normal guinea pigs or those with hearing loss,therefore ABR test can be performed without anesthesia to ensure the success and error minimization of the experiment.