Abstract
Research indicates that the addiction to fantasy among children with autism spectrum disorder negatively affects interpersonal communication. We provided occupational support to externalize the fantasy for a male child with a pervasive developmental disorder. This child was having difficulty executing activities of daily living due to immersive fantasy activities, which consisted of mentally forming a fictional card game as a diversional fantasy. For that reason, we externalized his fictional card game by writing out his imagined characters on actual cards and encouraged him to communicate with hospital staff and school friends using these cards. This support enabled him to mentally organize the fantasy, allowing him to use it as a communication tool. Moreover, he alleviated his troubles in daily living by reflecting on his fantasy and building a connection with reality.