The number of adults diagnosed with Autism Spectrum Disorder (ASD) have been increasing recently because they have difficulties of social functioning as adult. Characteristics, and treatment and accommodation in society of adults with ASD are reviewed in this article. The symptoms of ASD are discovered in the age of preschool and elementary school. Their symptoms have been sometimes disappeared according to their growing and they have not filled DSM-5 diagnostic criteria of ASD. However, there remains restricted topics, disability of empathy, and other ASD characteristics. Anxiety disorder and other psychiatric disorders are often found in adults ASD. Some show good social functioning if they are not affected with intellectual disability nor insisting on specific behaviors. ASD is thought to be syndromes with multiple genetic factors. About 30 years ago, the deficit of "Theory of Mind" was to be main cause of ASD. However, conjugate gaze is not developed in baby age, and persons with ASD cannot percept expression of face without concrete direction. So social motivation deficit is thought to be one cause of social dysfunction. We do not have medications to cure core deficits of ASD until now. Anti-depressants are used for anxiety or depressive symptoms and atypical anti-psychotics for self-injury or repetitive behaviors, although there is not robust evidence. Social skills training to enhance social learning is recommended though little evidence. So, both model to treat and social model to accommodate reasonably to environment are important. There have been increasing competitive employments in Japan owing to obligation to employ persons with disabilities. Adults with ASD try to insist their value system, and change rules or conditions flexibly which are determined by majorities in society, so that other persons with or without disability can work easily.
 Author's abstract