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 described as a clear-cut disease. The disease can be demonstrated by a chain of genetic locus dominant inheritance in the family, as evidenced by increased urinary hydroxyproline excretion in the patient, and is an elastin fiber defect, also known as an abnormality of collagen metabolism. The primary defect of the disease is unknown. It has been suggested that the lateral association between elastin and collagen tissue peptide chains is impaired, i.e., a lysyl oxidase defect. It is also associated with acidic mucopolysaccharide deposition, increased sialic acid, hyaluronic acid accumulation, and poor formation or excessive destruction of chondroitin sulfate. The incidence of Marfan’s syndrome causing high palatal arches is about 1/3000 to 5000 people, with more females than males, with no racial differences, mostly in children, but also in adults. Most patients have symptoms from birth. For the diagnosis of high palatal arch, we can start from its clinical symptoms: 1. Abnormalities of bone: spider finger (toe) is the main change of Marfan syndrome. Height and thin, long and narrow head, long and thin limbs, thighs and forearms for obvious, finger distance more than the length of the body, especially the fingers, long and thin toes like spider feet, feet often have obvious exostosis, individual hammer finger deformity. Sternal deformity is more common in funnel chest or chicken chest due to overgrown ribs, sometimes flat chest and winged scapular elevation. The spine is retrognathic and scoliosis, often limited to the thoracic spine. The trunk may be shortened by the lateral curvature and protrusion, making the extremities appear more elongated. 2. Ligaments and joints: laxity, increased joint movement marked hypotonia, hyperextension of joints, positive wrist sign. Systemic connective tissue abnormalities may involve the joint capsule, ligaments, tendons, and muscle membranes, which may lead to repeated joint dislocation, flat feet or high arched feet, high palatal arches, and uneven teeth. Repeated patellar dislocation and natural dislocation of the hip are also not uncommon. There are also inguinal and diaphragmatic hernias. 3. Appearance: It shows a sad appearance. The face is emaciated, weak and old, but the intelligence is normal, the ears are large and low, the outer ears are mostly deformed, the palatal arch is high, the brow arch is more protruding, and the eyes appear sunken. 4. Skin: Widened skin lines The most common skin manifestations are widened skin lines or atrophic skin lines. These skin abnormalities can be seen in many parts of the body, especially in the chest, shoulder deltoid area and thighs.