This research is the case study to investigate about interaction changes among family members after the family playing therapy in two families of Lou Gehrig’s disease’s victims. The research focused on not only these patients but also family members as the participants of the case study. The examinations were conducted basically once a week during eight weeks, sixty minutes per session. As the research material, the records of each examined session were collected and analyzed based on the Girogi’s phenomenological analysis method and by conducting the “before & after checking” the author tried to observe interaction changes within family members through family motivation and collaboration. The results of the research are following. Family members’ communication style was changed into positive communication, and family members’ emotion changed into positive emotion then finally relationship among family members was improved. Considering the changes in two families above, the family playing therapy gives the positive effect to interaction changes among family members of intractable patients.