This study examined the relationship between empathy, prosocial behaviour, social interactions and early psychopathological symptoms (internalising and externalising behaviours) in children with autism spectrum disorder (ASD) and typically developing (TD) children. A total of 506 parents of children aged 18–48 months participated in this study. The parents of 92 children with ASD and 414 neurotypical children completed the Empathy Questionnaire, the Child Prosocial Behaviour Questionnaire, and the Emotional and Social Development Questionnaire. The results confirmed the direct relationship between empathy and prosocial behaviour in both groups. However, the findings showed a different pattern of the indirect relationship between empathy and prosociality through the social dimensions in the children with ASD compared to their typically developing peers. In the children with ASD, there was only one significant indirect path from empathy to prosocial behaviour – through internalising behaviours (anxiety). Anxiety also played a moderating role in this relationship. The higher the anxiety, the stronger the relationship between empathy and prosociality. In the neurotypical group, social interactions were a significant mediator, strengthening the relationship between empathy and prosocial behaviour. Externalising behaviours weakened this relationship. Intergroup and gender differences were also examined. These findings may have practical implications for social skills training programmes based on behavioural interventions by highlighting the importance of prosocial behaviour for social interaction and protection against psychopathological problems in children with autism and typically developing children.