<p>This paper explores the application of 3D scanned data visualization to sandplay therapy, a popular form of psychotherapy. It also serves as an application paper for the recently proposed high-definition transparent visualization method, “stochastic point-based rendering.” Although 3D scanning has been successfully applied to various fields, such as designing and maintaining social infrastructure, digitally archiving cultural properties, and land-use planning, its application in psychotherapy remains underdeveloped. In sandplay therapy, clients with psychological issues create scenes by placing sand and miniatures in a tray. Therapists analyze these creations to gain insights and guide the therapy. Our aim is to develop prescriptions based on 3D visualization to assist therapists in analyzing the created sand tray scenes and to help clients reflect on their therapy. Specifically, we propose two types of visualization: one visualizes sand mounds using transparent visualization and the luminance gradient effect, and the other uses contour visualization in Cartesian and cylindrical coordinates to analyze sand shapes and miniature placements. As a case study, we visualized data from 3D scanned sand tray scenes created in actual therapy sessions and demonstrated that the proposed visualizations could provide valuable insights. The therapist can use 3D Scanning and Visualization to better interpret the clients’ mental state. This allows the therapists to see the data more objectively in a different form and clients can easily understand visual aspects of their mental states.</p> Graphical abstract <p></p>