This chapter presents an approach to the scientific concepts on autism, diagnosis, and treatment criteria, as well as the assessment of knowledge on this subject and its relationship with the level of health literacy in the context of Angolan society. To substantiate the importance of health literacy, dimensions of access, understanding and use of health information, and decision making, an observational case study related to a research carried out in 2012 for the tracking of signs of autism is explored. The sample consisted of a group of 200 mothers of children and adolescents who were initially diagnosed with intellectual disabilities. This sample, for convenience, was selected from students who had previously been diagnosed with intellectual disabilities and attended a public school located in the municipality of Rangel, in the Province of Luanda, capital of Angola. The current stigma still exists about the disease.