We treated midface hypoplasia in a 20-year-old woman with Crouzon syndrome using a rigid external distraction device. The patient showed severe exophthalmos and maxillary retrusion, although relatively good occlusion had been achieved by long-term orthodontic procedures. We considered that our patient's particular condition could not be resolved by the usual Le Fort III osteotomy/midface distraction procedure, so we devised a segmental approach. The midface, mobilized by Le Fort III osteotomy, was divided into two segments by Le Fort I osteotomy; each fragment was connected to the rigid external distraction device to be distracted separately. Distraction was begun after 1 day at 1 mm/day. The upper and lower segments were distracted over 17 and 12 days, respectively. The patient's occlusion was fully corrected, and her facial contour was significantly improved. After 3 weeks of consolidation, we removed the distraction device. The clinical course was without complication, and no relapse was observed on the cephalogram or computed tomography scan obtained 1 year after the procedure. Our modified technique was helpful in increasing the usefulness of the external distraction system and in refining the midface distraction procedure.