This article presents orthognathic treatment in successful collaboration with autotransplantation of the maxillary third molar. The case report describes a 24-year-old man with severe mandibular protrusion and severe crowding in both dentitions. Overbite was 0 mm, overjet, -15 mm. Maxillary second molars and mandibular third molars were extracted, and presurgical multibracket treatment was begun. Maxillary third molars were impacted completely at 18 months in terms of presurgical tooth alignment. Autotransplantation of the teeth was achieved to substitute for extracted maxillary second molars. At 6 months after autotransplantation, the maxilla was advanced 4 mm on both sides through a Le Fort I procedure; left and right sides of the mandible were set back 15 and 18 mm, respectively, via sagittal split ramus osteotomy to improve mandibular protrusion. The total treatment period lasted 37 months. Autotransplantation treatment is an effective modality for tooth replacement when a donor tooth is available. Fully impacted maxillary third molars are potentially reliable candidates for autotransplantation.