The mini-screw is widely used in orthodontic treatment for anchorage reinforcement. In mild skeletal Class III patient, retraction of mandibular dentition using mini-screw has been accepted as a reliable and stable treatment approach. In addition, the mini-screw placed in the retromolar area could be used for the uprighting of the lower molar. However, the placement of the mini-screw on the retromolar trigone or anterior ramus region need to be careful because of the possible risk of the “slippage” or “displacement”. Once the mini-screw is displaced to the fascial space such as pterygomandibular space, sub- mandibular space or lateral pharyngeal space, it is difficult to remove. In this case report, we present a mini-screw removal case via an intraoral approach that was displaced into the pterygomandibular space while placing the orthodontic mini-screw on the anterior margin of mandibular ramus.