Little is known about how parent health literacy contributes to health-related outcomes for children with autism. This mixed-methods study included 82 U.S. parents of a child with autism 2-5 years-old and sought to describe (1) health literacy dimensions, (2) how health literacy influences services use, and (3) health literacy improvement strategies. Results showed: autism information was accessed from multiple sources; understanding autism information involved "doing your own research"; autism information empowered decision-making; health literacy facilitated behavioral services use; health literacy influenced medication use; family and system characteristics also affected services use; autism education remains needed; services information is needed across the diagnostic odyssey; and greater scientific information accessibility would increase uptake. Findings demonstrate how parent health literacy affects services use.