Jaw malformation refers to the abnormal size, shape, and external placement of the jaws caused by congenital genetic factors and acquired environmental factors (i.e., diseases, oral habits, abnormal tooth replacement, etc.) during the growth and development of children. For example, underdevelopment of the lower jaw causes the lower jaw to recede, forming a lower jaw deformity, also known as “bird’s mouth” deformity; another example is the underdevelopment of the upper jaw, the middle third of the face is depressed, the front teeth are reversed (teeth together), and the side appearance is crescent-shaped or piggyback-shaped. In addition, there are cleft palate, maxillary and mandibular overdevelopment and abnormal lateral development of the jaws. Jaw deformity seriously affects facial aesthetics and can easily make adolescents have low self-esteem, which is not conducive to healthy physical and mental growth. These deformities are often difficult to correct, and most patients cannot achieve the desired effect by simple orthodontic treatment alone, and need to combine with orthognathic surgery. So when is the best time to correct jaw deformities? Is the earlier the better? The choice of when to treat jaw deformity should be based on the type of deformity, cause, severity, growth and developmental status, and other comprehensive considerations. For children with severe underdevelopment of the upper and lower jaws, measures should be taken as early as possible, such as anterior traction, to stimulate jaw growth with the help of the child being in the growth phase. However, for children with excessive jaw development, orthopedic treatment should be done after growth has basically stopped, for the following 2 reasons: first, the growth of the jaw is difficult to be inhibited, and clinical practice has shown that some inhibitory measures have been taken in time, but with little success; second, the growth and development of the child continues, and if the jaw deformity is corrected through orthognathic surgery, the deformity may reappear with the growth and development of the jaw. For some serious jaw deformities, if left untreated, they will affect the function of the oromandibular system, such as feeding and pronunciation, etc., they should be treated as early as possible to avoid nutritional deficiency and pronunciation disorders. Therefore, if children have the above jaw deformities, they should go to the hospital for examination as early as possible, listen to the doctor’s advice, and never miss the best time for orthopedic treatment.