Autistic youth demonstrate an overestimation of competencies when compared with neurotypical (NT) peers. Research has also shown NT males/boys tend to overestimate their competencies more than NT females/girls. This study assessed sex differences in autistic youths' overestimations on academic self-perception variables. Notably, 127 (70 male) autistic youth ages 9-18 years completed two academic tasks (one verbal and one mathematics) and estimated their performance pre- and post-task. Males overestimated their competencies to a higher degree than females on pre- and post-verbal task measures but not on mathematics measures. The results support the previous findings on sex differences in autistic self-perception patterns. Implications for special education are discussed.