Abstract:The purpose of this study is to discuss the effects of the Chinese medicine six-flavor Rehmannia Decoction with additives on preventing deafness induced by gentamiein (GM) in guinea pig by means of testing the thresholds of Preyer‘s reflex (PR) cochlear microphonic potential(CM), action potential of the auditory nerve (N1)and scanning electron microscope of inner ear (SEM). The results showed that the medicine is effective in reducing the ototoxic effect of GM on inner ear.