The conventional treatment of skeletal Class III malocclusion has been focused on application of orthopedic force primarily to the mandible. However, In Class III malocclusion with retrograde position or underdevelopment of Maxilla, this approach is not suitable treatment. These patients need an application of orthopedic forces via face-mask to the Maxilla to stimulate its growth and to change the direction of growth. In skeletal Class III patients who were treated by Face-Mask, the following results were obtained. 1. Forward growth of Maxilla was enhanced. 2. Labioversion of upper incisors and linguoversion of lower incisors were observed. 3. Mandible was rotated to clockwise direction and remodeling of B point was observed. 4. Anterior crossbite was corrected by combining of the above results.