Jaw cyst is a common bone cyst affecting the jaw. Clinically, fenestration decompression is the first choice for treating jaw cysts in children, but traditional strategy still has limitations in positioning accuracy, potential trauma, adherence, etc. This study designed an improved strategy, three-dimensional digital guide plate-based fenestration decompression with sustained plug for the treatment of jaw cyst in an 8-year-old boy. After the surgery, the cyst gradually became smaller and disappeared at 1 year, permanent teeth erupted normally and the wound healed well. Under the positioning of three-dimensional digital guide, the position of fenestration was accurately located, and the anatomical structures in the cyst cavity were protected. The wound was small in size, and the postoperative pain response was mild. Additionally, the expanded structure of the plug at both ends made it firmly fixed in the opening position. The plug could be rinsed daily with simple operation and no pain, avoiding discomfort caused by repeated wearing. To sum up, the improved strategy is effective in the treatment of jaw cyst.