Abstract: Background: Autism is a complex neurobiological development disorder that includes disorders of aspects of social interaction, communication, language, behavior, emotions and sensory perceptions. Children with autism who experience developmental delay will feel difficulty in the ability to socialize with the environment. Some therapies that can be done are behavioral, speech, occupational, physical and play therapy. Role play therapy in early childhood can improve social ability. Role play can cultivate empathy, sympathy and enhance cooperation with others. Purpose: This study aims to determine the influence of role play on the development of autistic children in SLB Negeri Semarang. Methods: The research design was pre experiment with pre-post test design approach. Sample study was 34 children with autism. Pretest was done by assessing child development. Intervention was done on the second, fourth and sixth days after the pretest. Post test was done on the eighth day. Developments were observed based on Gilliam Autism Rating Scale. Role play was done by asking the child to play a role with the theme of health in pairs. Intervention was done 3 times in 1 week for 5-10 minutes. Wilcoxon test was used for Data analysis. Finding: The results showed that there was an influence of role play on the development, before the role play 11.8% of good development and after the role play showed 20.6% good development. When children perform role plays, interaction occurs with others, practice improving speech and listening skills and the ability to express feelings. Conclusion and Recommendation: An Influence of role play on the development. Role play can be used as a therapy for children with autism.