Many surgical techniques have been applied toward correcting the prominent mandibular angle. One of the most popular methods is mandibular angle ostectomy. However, gross asymmetry, mandibular condylar fracture, and unnatural contouring of the mandibular angle are frequent consequences. Therefore, we perform ostectomy of the lateral cortex around the mandibular angle in patients with wide and squared lower faces. Seventeen female patients with ages ranging from 23 to 35 years underwent surgery. Ostectomy of the lateral cortex of the mandible and mandible angle ostectomy were performed in five patients (group I). Ostectomy of the lateral cortex only was performed in the remaining 12 patients (group II). The follow-up period ranged from 1 to 5 years. Postoperatively, the bigonial distance was effectively reduced in both groups (group I, mean 13 mm; group II, mean 12 mm). Compared with group I, the gonial angle and mandibular plane-sella-nasion angle were within normal ranges in group II. We therefore conclude that the ostectomy of the lateral cortex alone allows the reduction to be achieved without changing the angle of the mandible itself. Moreover, although the resection of the mandibular angle was not performed, the contour of mandibular angle became soft, giving a more natural appearance.