Objective Adults with autism spectrum disorders (ASD) experience significant difficulties with executive functioning (EF) and related adaptive skills, yet the lack of interventions in South Korea targeting these areas has resulted in a heightened need to develop an evidence- based program. Therefore, we developed a novel intervention aiming to enhance everyday EF and daily adaptive skills in adults with high-functioning ASD and conducted a pilot study to evaluate the validity and feasibility of the program. Methods A behavioral intervention of 10-weekly sessions was developed based on literature searches and focus group interviews. Seven adults with high-functioning ASD (mean age=20.29) participated in a single-group pilot trial. We used self and parent-report questionnaires as well as skills measured by assessment instruments to analyze differences before and after the intervention. Results Significant improvements were shown in everyday EF, including time management, organization, self-restraint, and regulation of emotions. Additionally, results demonstrated an enhancement in adaptive functioning, especially in the subdomains of daily living skills. Analyses of parental outcomes only revealed a significant decrease in the scores of emotion regulation. Conclusion The current study provides good evidence for the validity and feasibility of an intervention to improve everyday EF and adaptive skills in adults with ASD.