Is there a difference in sense of agency between children and adults? This study investigated the difference in the time window of sense of agency between school-age children (N = 94, aged 6–12 years) and young adults (N = 30, aged 21–23 years) by using an agency attribution task and international standardized manual dexterity test. The results showed that the time window for sense of agency was ... [Show full abstract] significantly shorter in children compared to young adults. In addition, there was a significant correlation between the time window for sense of agency and manual dexterity only in children. The present results suggested that sensory-motor function greatly contributes to sense of agency in school-age children.