There were not many studies to provide information on health access and health utilization of people with autism spectrum disorders (ASD). The present study describes a general profile of hospital admission and the medical cost among people with ASD, and to analyze the determinants of medical cost. A retrospective study was employed to analyze medical fee of 397 individuals with ASD based on population-based National Health Insurance (NHI) claims data in Taiwan. The average frequency of hospital admission in the respondents was 3.5 annually, mean of hospital stay was 111.9 days, and the mean medical expenditure was 94,293 NTD in the year of 2005. Those autistic individuals with characteristics of younger age (OR=31.085, 95% CI=12.772-75.659), hold a serious illness card (OR=4.980, 95% CI=1.690-14.673), more frequent in inpatient care (OR=7.636, 95% CI=2.643-22.066), longer days in acute ward (OR=3.840, 95% CI=1.989-7.416), and days in acute+chronic wards (OR=3.804, 95% CI=1.334-10.846) were more likely to consume more medical expenditure than their counterparts. The present study provides valuable medical care utilization information to health care decision makers to initiate a supportive healing environment for people with ASD. (Contains 4 tables.)