Background: Increase in mobile phone users cause extensive consideration of researchers to biological effects of mobile phone waves. As the mobile set, is held near the ear and temporal lobe, and whereas distance of antenna from the inner ear is few centimeters, this study is the first research in our country to assess potential changes in auditory brain stem response of rabbit after exposure to mobile phone waves from a simulator.   Materials & Methods : This study is experimental. In conducting the experiment, were used male rabbits. The method used was, auditory brainstem response (ABR), which is the usual method in detecting changes in retrocochlear and acoustic pathway. Before and after animal's exposure (one and two weeks), latency time of the fifth wave of ABR were measured and recorded with two stimuli, click and tone burst (at different frequencies) in two intensities of 70 and 100 dB.   Results : At the end of first week the latency time of wave V (ms) increased for all the frequencies of the experiment, especially at the (2000-4000 & 8000Hz). An increased of more than 0.2 ms was noticed. It was caused at least 10 dB deficiency in hearing. But at the end of second week of exposure, the latency time of wave V, at the frequencies of 500 and 1000 Hz, was almost unchanged but at the frequencies of (2000-4000 & 8000 Hz) was decreased more than 0.2 ms and was nearly the amount of pre-exposure. Statistical analysis of results has not shown significant changes between latency time of wave V (ms), in pre and post exposure (p>0.05).   Conclusion : This decrease in 2000-8000 Hz frequencies at the end of second week can be viewed as adaptation of animal's hearing at high frequencies. Although for confirm it need to research more and longer.