Distraction osteogenesis for the advancement of hypoplastic maxilla of cleft patients has shown successful results. In this report, rigid external distraction(RED) system and internal distraction device were used for maxillary advancement. Each system has its advantages and disadvantages. Larger amount of advancement can be achieved with RED system. But complex external device may give patients psychological stress. Internal device is invisible. However its distraction amount have limitation for the advancement (< 20mm) and the vector cannot be changed freely during distraction. The authors treated five cleft patients with maxillary hypoplasia(three with RED system and two with internal distractor). Their results were clinically satisfactory. We present the pros and cons of RED and internal system for maxillary distraction osteogenesis.