The purpose of the current study was to compare the 1-year stability of skeletal after original Le Fort I osteotomy and maxillary step osteotomy. Fifty-two patients with prognathism underwent sagittal split ramus osteotomy with either original Le Fort I osteotomy or maxillary step osteotomy (26 patients each). Twelve cephalometric parameters were measured to evaluate postsurgical stability (lesser change was considered as enhanced stability) at 1 month (T1), 6 months (T2), and 1 year (T3) postoperatively. Only 3 parameters-vertical and horizontal distance of menton and vertical distance of point B-showed minimal but significant differences between the two groups. Lesser degrees of changes were observed after maxillary step osteotomy than after original Le Fort I osteotomy, and the differences were significant during the period between T1 and T2, but not from T1 to T3. Differences between the two groups were less in asymmetry cases required correction of the occlusal plane. In conclusion, differences between original Le Fort I osteotomy and maxillary step osteotomy were observed at the frontal points of the mandible; however, they were not clinically significant. It may be suggested that there is no significant difference in skeletal stability at 1 year after the two procedures.