Objective To assess hearing and efferent system functions of autistic children.Methods Tests were performed on 30 Autistic children and 15 normal children to evaluate hearing objectively by using otoacoustic emission (OAE) and auditory brainstem response (ABR).The efferent system functions were analyzed through contralateral suppression in OAE.Results The mean ABR Ⅰ-Ⅴ interpeak latencies (IPLs) in children with Autism were significantly reduced than that in the control group.The amplitudes of OAE at 1 kHz and 2 kHz in autistic children were significantly different in two groups.There were no significant differences in contralateral suppressions between the Autistic children and the control.Conclusion Hearing impairment may be more common in children with Autism than in normal children,while for a few Autistic children,their efferent system functions are affected.