This pilot study explored the efficacy of a social-cognitive intervention program for adolescents with Autism Spectrum Disorder (ASD). Seven adolescents with ASD (mean age = 12.57 years) attended a school-based 10-week program. Social Skills Improvement System Rating Scales, Goal Attainment Scaling (GAS), and Theory of Mind Inventory were administered at baseline, immediately after the program, and post 2-months. There were significant positive gains in Theory of Mind knowledge and in individualized goals (of GAS), and there were further gains after 2 months. Qualitative evaluation was conducted by a focus group interview with parents of participants. Consistent with the quantitative findings, parents observed that their children have increased knowledge of social skills, socialize more with friends, and had increase in positive social behavior. On the other hand, they perceived an even more intensive and ongoing program could further benefit their children. This study has added to the understanding of the potential impact of social skills programs run in school.