Two-day old chicks were given gentamicin (GM) and kanamycin (KM) for 10 days and then the cochleas were processed for both scanning electron microscopy and light microscopy on the same day and in 1, 2, 3, and 4 weeks following the last injection to examine hair cells regeneration and recovery. The result showed that hair cell loss was up to 40% in the base of the basilar papilla following GM and KM administration. One week after injection, however, most of the damaged region was replaced with regenerated hair cells. Three to four weeks later, the regenerated hair cells were developed into normal sensory hair cells. This experiment demonstrated that the hair cells in the chick cochlea were able to regenerate and recover following GM and KM induced damage.