The head-up tilt test (HUTT) is a test for the diagnosis and typing of vasovagal syncope (VVS) and the differential diagnosis of postural tachycardia (POTS) and upright hypotension (OH) in children by changing the position of the patient (from lying down to a certain angle of tilt). Before performing the HUTT test, the physician should ask the child’s syncope history in detail, including the form of syncope, triggers and precursors of syncope, etc.; understand the child’s previous test results related to syncope; inform the child and his parents of the significance of the HUTT test for the diagnosis of syncope in children, the safety of the test and the possible psychological discomfort or adverse reactions of the child, etc., to eliminate the anxiety of the child and his parents about the test. The test is performed on the child 3 days before the test. The child should stop taking drugs that may affect autonomic function 3 days before the test according to the physician’s advice; fast for 12 hours before the test, and do not use caffeine-containing food for the last meal to avoid affecting the test results. During the HUTT test, medical staff monitor the child’s ECG and blood pressure, and closely observe the child’s clinical performance and changes in heart rate and blood pressure to determine whether the child has precursors of syncope or syncope, and terminate the test in a timely manner. Usually the clinical symptoms, heart rate and blood pressure returned to normal within a few minutes after the child returned from the tilted position to the lying position. After the test, the physician will propose a treatment plan for children with positive HUTT reactions: one of the health education and physical training counseling: inform the parents of the need to pay attention to the proper intake of water and salt in the child’s daily diet, the possible triggers of syncope (such as high temperature, dehydration, overexertion, prolonged standing, etc.), the emergency measures to be taken in case of syncope precursors or syncope at home or at school, etc. The second is that according to different conditions, some patients need to choose appropriate drugs for treatment along with physical training.