Objective: The purpose of this study was to investigate the effects of craniofacial structures in young adults Class III skeletal crossbite by combined of the removable and/or fixed appliances. Materials and Methods: 24 cases young adults ( 18-24 years old) with skeletal crossbite were chosen as this clinical study. All of cases have been treated by suitable appliances and new mechanic orthopedic system. Namely upper jaw used the removable appliance for protraction in the night, then the lower jaw applied the fixed one for Class III elastics in day time. Otherwise, the upper jaw used fixed appliance, such as screw rapid expansion at the same time of protraction, the lower jaw approached the removable appliance with hooks and occlusal pad for Class III elastics. The force of face-mask protraction is over 800 gm and Class III elastic is of 300 gm for each side. Results: All of the patients have been treated smoothly and affected since face-mask protraction and Class III elastics alternately in day and night. The craniofacial structures were influenced nearly the whole day of 24 hours. Pretreatment and posttreatment of lateral cephalograms were traced and analyzed. Statistically significant anterior movement of maxilla occurred in SNA(+2.77) and ANB?+3.48?.The mandible was rotated clockwise with mild decrease in SNB(-0.71). Soft tissues were changed remarkably in upper lip moving forward(+2.1mm) and lower lip moving backward(-1.5mm). Conclusions: The results of this clinical study indicate that the young adults Class III skeletal crossbite were affected by application the removable and/or fixed appliances and an new machenic orthopedic system.