Objective To study the feasibility on three dimensional printing guide plate in surgery-first-orthodontic-approach for maxillofacial asymmetry and to evaluate the effect. Methods 6 patients with dento-mandibular deformities underwent spiral CT scan to collect raw data and laser scan for the dentures were performed. The data from CT scan and laser scan were imported into ProPlan CMF software. The preoperative planning including segmentation, osteotomies, and movements of the jaw bones was simulated using the ProPlan CMF. The digital guide plates were fabricated by three dimensional printing. The model surgery for each patient was performed at the same time and the traditional surgical plates were made. Two kinds of plates were brought to the operating room during the surgery to compare the two methods of preoperative planning and fabrication of the plates. Results Most of the three dimensional printing digital guide plate worked well with mandibular surgery. 5 patients were shown to be good for predicting the effect of surgery. The 3-month follow-up results showed the patients were satisfied with their appearance and had no complications including TMJ disorder. Conclusion Three dimensional printing digital guide plate is valuable in precisely simulating osteotomy, contributing to understand surgery-first-orthodontic-approach for mandibular asymmetrical patients.