Abstract: One of the interventions, of which effectiveness in the teaching of social skills has been examined in autism literature in recent years, is teaching with cool versus not cool. In this study, it was aimed to examine the effectiveness of teaching with cool versus not cool in the teaching of social skill ("Coping with inappropriate requests from familiar peers or adults") to participants with autism spectrum disorder (ASD). A multiple probe design across participants was used to investigate the effectiveness of teaching social skills with cool versus not cool. In the study, follow-up data after 1, 4 and 10 weeks, and across-settings generalization data were collected from participants with ASD. Furthermore, social validity data were collected from participants with ASD. The findings of the study showed that all participants acquired and preserved social skills. In the study, it was observed that the first and second participants generalized the skills they acquired to different environments. No generalization data were collected for the third participant. The social validity findings collected with the subjective evaluation approach revealed that the participants' opinions about the target skill, the teaching process and post-teaching performance were positive. It was observed that the findings of the study were in parallel with other research findings related to the subject, and suggestions for the intervention and further studies were made.