Purpose <p>Social difficulties are fundamental aspects of autism spectrum disorder (ASD). However, behavioral issues such as attention difficulties, thought problems, externalizing behaviors, and internalizing behaviors can further hinder children's ability to develop social skills. We aimed to explore how co-occurring behavioral challenges may intensify social difficulties in autistic children and adolescents by assessing whether a higher prevalence of behavioral problems is associated with poorer social functioning in real-world scenarios.</p> Methods <p>We surveyed parents of 225 children diagnosed with ASD. Parents completed two questionnaires—the Child Behavior Checklist (CBCL) measuring psychiatric symptoms, and the Social Skills Improvement System (SSIS) assessing observable social abilities. We statistically analyzed the connection between behavioral scores and social scores.</p> Results <p>The results showed that more severe behavioral issues on the CBCL tied to weaker social skills overall on the SSIS. Among all behavioral domains, attention problems showed the strongest negative associations with total social skills and all subdomains. Thought problems also demonstrated significant negative association with several aspects of social functioning. Externalizing behaviors and internalizing behaviors were also negatively associated with social skills, though their effects were less pronounced than those of attention and thought problems.</p> Conclusion <p>Our findings provide real-world evidence that common co-occurring behavioral problems especially attention problems and thought problems showed strong negative associations with social skill difficulties in autistic children and adolescents. Screening for and adjusting conditions like attention problems, thought problems, and disruptive behaviors may be an important piece of helping autistic children build social competence.</p>