This study uses the method of action research to explore the process and results of four high-grade elementary school single-parent children’s loss adjustment, who participating in the “playfulness -based positive counseling group with LEGO Six Bricks and Play Box” once a week, for 75 minutes each time, for eight consecutive times. The researchers collected group records, researcher reflection notes, discussion records, interview records, feedback and analyzed them through the triangulation method. The results of the study found that at the beginning, promoting positive emotions through group activities can help members quickly invest in the group, and then by practicing the strengths perspective, members can see and give back to their own and others’ strengths, and build positive resources and positive attitudes. Interpersonal relationships, and at the same time practice seeing gratitude in loss events, reducing negative evaluations of oneself, extending gratitude to life, linking family resources through parent feedback sheets, deepening advantages in the family with parents, and forming a parent-child relationship. The positive interaction between them increases the sense of meaning and happiness. The real-time reflection and revision during the research process enables researchers to grow in consultation group program design, professional knowledge and problem-solving ability, and provides suggestions for counseling practitioners and future researchers.