Several surgical and/or orthodontic procedures have been used in maxillary protraction. Currently procedures with the use of distraction osteogenesis have been studied by many investigators and applied to various clinical situations and this procedure is rapidly becoming an alternative technique to treat craniofacial growth disturbances and dysplasias. So we performed distraction osteogenesis for 12-year old young patient with maxillary hypoplasia and 7-year old young patient with severe maxillary deficiency due to unilateral cleft lip & palate. First we performed incomplete Le Fort I osteotomy (pterygomaxillary dysjunction and no maxillary downfracturing) and then tried to protract the maxilla by way of extraoral device, Delaire type face mask. During the follow-up period of 12 months and 13 months respectively, we could attain the successful results by analysis of lateral cephalometrics in facial profiles. So we suggest that this maxillary distraction technique is one of the excellent therapeutic choices in the treatment of growing children with maxillary deficiency.