Purpose: For many individuals with autism spectrum disorder (ASD), postsecondary outcomes are poor. This may be due to insufficient academic supports, particularly with regard to literacy skills, during high school. More information is needed about skill profiles so that we can better differentiate support for students with varying social, communication, cognitive, and academic proficiency levels. This study was designed to (a) identify unique literacy profiles of high school students with ASD, (b) assess profile stability over time, (c) identify predictors of profile membership, and (d) analyze stakeholder reports of required school support intensity. Method: Participants were a diverse sample of high school students with ASD, 14-21 years old (N = 544), their parents, and their teachers who participated in a randomized controlled trial of a comprehensive treatment model for high school students with ASD. Standardized measures were administered to assess nonverbal IQ, autism symptomatology, language/adaptive communication, reading comprehension, academic knowledge, and parent/teacher report of school support needs intensity. Latent transition analysis was conducted to examine sample heterogeneity and to explore the stability of the profiles. Associations between profiles and reports of support intensity were examined. Results: Four literacy profiles were identified that were stable over 2 years: Emergent Literacy/Comprehensive Support, Low Literacy/Intensive Support, Average Literacy/ Moderate Support, and Average Literacy/Limited Support. Parent and teacher reports of school support intensity generally aligned with the profiles. Conclusions: These analyses provide insight into the diverse literacy and support needs in ASD. Implications for practice and the role of speech-language pathologists in assessment and intervention are discussed.