Background & Objectives: Hearing disorders are the most common causes of pediatric communicative and functional disorders in the united states which result in communicative and learning disorders, educational failure and vast socio-economic problems. It is estimated that the incidence of hearing loss in pediatric population is 2-4% and otitis media, which is the second infectious cause after the ordinary cold, is the most common cause of hearing loss in children. Hearing loss is categorized into two distinct groups, namely conductive and sensorineural, the former being more common among children. Most of the causes for conductive hearing loss can be diagnosed and treated. Hence, majority of hearing loss cases can be prevented by taking appropriate measures. This study was performed to examine the incidence and common causes of hearing loss among school children in Ardabil.

 Methods: This cross-sectional study was performed on 1999 primary school boys and girls (grades 1-5). The data were collected through a questionnaire in the from of autoscopic examinations and Tuning Fork tests. 654 cases were referred to the audiometric and tympana metrics centers for further examinations as well as filling out the questionnaires. 483 (24.2%) students were definitely suffering from hearing loss. The data were analyzed through descriptive statistics and SPSS software.

 Results: In this study, the hearing disorders of male students was more than female ones. The most common causes of conductive hearing loss in both sexes and all 5 grades was cerumen (50.3%) and the second cause was otitis media with effusion (34.6%). The incidence of sensorineural hearing loss was 1.86%. Hearing loss disorders in low socioeconomic households is high (44.1%). There was a meaningful relation between hearing loss disorders and positive family history, educational failure, social class and seasons (p=0.001). Hearing loss disorders are high during the cold seasons (73.90%).

 Conclusion: Regarding the high prevalence of hearing loss among school children, more extensive and interventional studies as well as wide ranging screening are required.