OBJECTIVE: To analyze the thresholds obtained in the testing of auditory evoked potentials (PEATE) by air and bone conduction in children younger than 15 months old, with agenesis of external auditory canal. MATERIAL AND METHODS: We evaluated 22 children, seven girls and 15 boys, aged between 2 and 12 months old with agenesis of the external auditory canal. We research the potential brainstem auditory evoked by air and bone via at frequencies of 500Hz and 2000Hz. Equipment used Smart EP, brand IHS. RESULTS: The electrophysiological thresholds obtained by bone conduction in all children were within normal values, demonstrating the integrity of the inner ear. In search of the airway, the threshold values presented changes, an increase of absolute latencies in all ears investigated and there was no increase in interpeak latencies. The analysis of the PEATE by air in conjunction with the bone, increase the possibility of a more accurate and early diagnosis. CONCLUSION: We found that the conductive hearing loss does not influence the electrophysiological thresholds obtained by bone conduction through the PEATE. The research of PEATE by bone is an important tool to assess cochlear integrity in children with agenesis of the ear canal, less than 12 months old.