Objective: Multiple sclerosis (MS) is a neurological disease that causes sudden deaf. In this research auditory disorders were studied in the patients with multiple sclerosis (MS).

Materials & Methods: This cross sectional descriptive-analytical study was performed on 107 patients with multiple sclerosis in the range of 20-45 yrs. There were not history of trauma and middle ear disease in all cases. Sampling was randomized. A complete auditory evaluation including pure tone audiometry, speech audiometry, imittance audiometry and brainstem Auditory Evoked Potential were performed on patients.

Results: In pure tone audiometry 62.19% of cases had sensory neural high tone loss. In speech audiometry and imittance audiometry 18 and 31 cases were abnormal, respectively. 14.55% of cases had abnormality in BAEP. The most of abnormalities were prolonged latency of V, decrease of V/I amplitude ratio and poor reproducibility, respectively. With high rate of stimulation 57.77% of cases were abnormal. Statistical analysis showed significant difference between latency of V and stimulation rate.

Conclusion: According to findings of this research it seems that hearing evaluation is very important for follow-up and early rehabilitation of auditory disorder in patients with MS. Also auditory tests battery especially brain-stem auditory evoked potentials (BAEP) with high stimulation rate are useful in the diagnosis of Multiple Sclerosis.