A case was presented with an adult male patient diagnosed as skeletal class Ⅲ and dental class Ⅰ malocclusion, and complaining of his dental crowding. Undergone orthodontic related examinations and periodontal evaluations, the treatment plan was to combine atypical extraction with insertion of mini-implants into mandible, in order to facilitate control of anchorage. After the treatment, lateral profile and occlusion were both apparently improved. Discussions were made about usage of mini-implants in this case and other possible ways to treat the patient.