Syncope is a transient state of loss of consciousness caused by a transient lack of cerebral blood supply. The attack is sudden and the child often falls to the ground due to loss of muscle tone and inability to maintain normal posture, which usually lasts for a few seconds and can quickly return to normal. Syncope is a common emergency in childhood, and its incidence is on the rise, accounting for 1% of pediatric emergencies, often causing unintentional injuries in adolescents and receiving social, family and clinical attention. There are many etiologies leading to syncope in children, including neurally mediated syncope, cardiogenic syncope, metabolic syncope, and psychogenic syncope. Vasovagal syncope is one of the most common causes of syncope, accounting for about 60-70% of all syncope, mostly seen in older children and more common in adolescent girls. It usually manifests itself as a syncopal episode induced by prolonged standing (mostly occurs during the flag-raising ceremony on Monday), exercise or stress in the affected child, and may be preceded by brief dizziness, inattention, pallor, decreased visual and auditory perception, nausea, vomiting, and cold sweats. Upright tilt test is a recognized and effective method to diagnose vasovagal syncope, including basic and sublingual nitroglycerin excitation test, method: stop all drugs affecting autonomic function three days before the test, fast 12 hours before the test, the test requires quiet, dim light, appropriate temperature, use of polyphysiological monitor to continuously monitor the electrocardiogram, blood pressure changes, and regular recording, the emergence of symptoms continuously The patient should lie flat for 10 minutes and then adjust the tilted bed to 60 degrees until positive symptoms appear or 45 minutes to complete the whole process, if negative, sublingual nitroglycerin 4-6ug/kg in the tilted position, and observe for 20 minutes or when positive reaction appears. Treatment of vasovagal syncope: health education, basic therapy, medication, pacemaker therapy, etc.