Objectives: In the first place, to evaluate skeletal changes of the maxilla and mandible induced by surgical-orthodontic correction of malocclusions class III with long-face syndrome and secondly, to analyze the stability of these skeletal changes in the long term (more than 6 years). Design of Study: A retrospective, unicentric and longitudinal study of 19 patients who had undergone surgical and orthodontic therapy for class III skeletal malocclusion with long-face syndrome was undertaken. A cephalometric analysis based on 8 angle measurements, and statistical analyses at three different points in time (before orthodontic treatment, after orthognathic surgery and after a retention period of at least 6 years) were carried out. Results: The changes produced following surgery show that, with the exception of the maxillary plane and the facial axis, all other variables presented changes of great statistical difference. Conclusions: Skeletal changes after orthodontic-surgical correction present maxillary advance, mandibular regression and mandibular anterorotation. The angles that represent the mandibular vertical position (ramus angle, goniac angle and mandibular plane angle) showed statistically significant relapses and no stability in contrast to the facial axis.