The present study examined individual differences in theory of mind (ToM) among a group of 60 children (7-11 years-old) with autism spectrum disorder (ASD) and average intelligence. Using open-ended and structured tasks to measure affective ToM, cognitive ToM, and spontaneous social attribution, we explored the nature of ToM and assessed whether ToM predicts the phenotypic heterogeneity in ASD through structural equation modeling. Affective ToM uniquely predicted social symptom severity, whereas no ToM types predicted parent reported social functioning. Our findings suggest that differentiating among theoretical components is crucial for future ToM research in ASD, and ToM challenges related to reasoning about others' emotions may be particularly useful in distinguishing children with worse social symptoms of ASD.