A typically developing student's perceptions of his or her own capabilities (academic self-concept), is predictive of later academic achievement. However, little is known about academic self-concept in youth with autism spectrum disorder (ASD). To understand whether students math self-concept and reading self-concept predicted their performance, 44 school-aged children and adolescents with ASD and 36 age-matched individuals with typical development (TYP) rated their perceived math and reading abilities and were administered standardized achievement measures. Results showed self-concept was predictive of performance in math and reading in the TYP group. For youth with ASD, there was agreement between self-concept and performance only in math. These findings suggest that educators should be cautious when interpreting the self-assessments of reading ability in students with ASD.