This study explored the sandplay therapy case of a middle school-aged boy having severe conflicts with his mother from the viewpoints of initiation. The goal of the therapy was to lessen the boy’s conflicts with his mother within the free and protected space in sandplay therapy. Thirty-seven therapy sessions were held. The client showed the scene of having fun in the water in the most unconscious part of the tray in the initial phase of therapy (1, descending into the unconscious). In the intermediate phase of therapy (2～33, a period of suffering, confrontation with death and trials), he showed suffering, was confronted with death and underwent trials. In the final phase of therapy (34～37, seeking masculine principles and rebirth), he began to seek masculine principles instead of having conflicts with his mother and was reborn. Using sandplay therapy in a free and protected space, this study showed the effectiveness of sandplay therapy since the boy’s severe conflicts with his mother were lessened. This study also confirmed the existence of an archetypal pattern in a male adolescent’s psyche.