School absenteeism is a major societal problem, with a range of potential adverse long-term consequences. This scoping review aimed to provide a comprehensive overview of the research on school absenteeism in autistic children and adolescents, expose important gaps in the literature, and explore possibilities for future systematic reviews. Five relevant databases were searched systematically from inception to June 2023, yielding a total of 46 eligible reports from 42 separate studies. All studies were conducted in high-income countries, and most were published in the last decade. Three major themes emerged: occurrence, contextual factors, and interventions. The results of large-scale population-based studies clearly suggested that autistic children and adolescents were absent from school more often than their non-autistic peers, which partly was attributable to co-occurring conditions. Bullying also emerged as a potential risk factor. Only a few preliminary studies were available on targeted interventions, emphasizing the need for more robust studies. More research is also needed on the mechanisms leading to and maintaining school absenteeism in this group of learners. Overall, the diversity of research questions, methods, and definitions used in this body of research suggests that systematic reviews with narrow focus on a few key questions may still be premature.