High palatal arches are mostly seen in Marfan’s syndrome, mainly with elongated limbs, spider fingers (toes), arms extended flat with finger spacing greater than the length of the body, hands hanging down over the knees, upper body longer than the lower body. Long head deformity, narrow face, high palatal arch, large and low ears. Little subcutaneous fat, underdeveloped muscles, wrinkled skin on the chest, abdomen and arms. The muscle tone is low, with an inert body type. Ligaments, tendons and joint capsules are elongated and lax, and joints are hyperextended. Sometimes funnel chest, chicken chest, kyphosis, scoliosis, and spina bifida are seen. Cardiovascular lesions mainly invade the aorta, aortic valve and mitral valve and are the main cause of death. Since this disease is very characteristic, it can be said to be instantly recognizable. High palatal arch is the main manifestation of Marfan’s syndrome. The main danger of this disease is cardiovascular lesions, especially the combined aortic aneurysm, which should be detected early and treated early. The diagnosis can be made based on the clinical manifestations of the three main signs of skeletal, ocular and cardiovascular changes and family history. There are two clinical types: those with all three main signs are called complete; those with only two are called incomplete. The simplest means of diagnosing Marfan’s syndrome is echocardiography, which can be performed in all cases of suspicion, and MRI (magnetic resonance imaging) is required for further confirmation. In younger, taller patients with pneumothorax, physical examination and family history should be noted to exclude the possibility of coexisting Marfan’s syndrome. Marfan’s syndrome is diagnosed if the patient has a family history and typical aortic root dilatation, aortic coarctation aneurysm, mitral valve lesion and lens prolapse with positive skeletal signs. In the 1996 revised diagnostic criteria for Marfan’s syndrome, several major and minor criteria are listed in the skeletal, ocular, cardiovascular, pulmonary, skin and body envelope, dura (spinal) membrane, and family genetic history, respectively, and those without family or genetic history need to have major criteria that match more than two different systems and involve more than three points of organs to confirm their diagnosis of Marfan’s syndrome.