Sustained autonomic arousal during eye contact could cause the impairments in eye contact behavior commonly seen in autism. The aim of the present study was to re-analyze the data from a study by Kaartinen et al. ("J Autism Develop Disord 42"(9):1917-1927, 2012) to investigate the habituation of autonomic arousal responses to repeated facial stimuli and the correlations between response habituation and social impairments among children with and without ASD. The results showed that among children with ASD, the smaller the habituation was, specifically in responses to a direct gaze, the more the child showed social impairments. The results imply that decreased autonomic arousal habituation to a direct gaze might play a role in the development of social impairments in autism.