Children with autism spectrum disorder (ASD) are at risk for disrupted peer interactions. This study contributes to our understanding of how multiple foundational elements of emotional competence are related to children's prosocial behaviors with peers. Children with ASD demonstrated significantly lower non-stereotypical affective perspective taking, had lower ratings of emotion regulation, and showed differences from their typical peers in the use of discrete coping strategies during peer interactions. Children's emotion regulation and use of discrete coping strategies in the context of peers were associated with their prosocial behaviors one year later. The findings add to our understanding of how emotional development contributes to individual differences in the social-emotional behaviors of children with ASD. Implications for intervention are discussed.