Abstract
This research was based on a case study of a child who experienced difficulties in ego development due to her mother's compulsive and depressed behavior. Twenty-four therapeutic play sessions, including 16 sessions involving sandplay, were conducted. Based on discussions by Neumann and Kalff, the child's early psychic development and ego development were observed during these sandplay. As part af this investigation, I conducted counseling sessions in the sandbox where the atmosphere was free and safe. The sessions were based on mother-child unity with the therapist. As a result, the child exhibited restoration of mother-child unity and showed the journey of constellation of self and ego development. The results of this research indicate the effectiveness of sandplay in accelerating ego development.