There are many reasons why children hit themselves, probably for the following reasons: first, there may be temper tantrums, character defects caused by some children are more introverted, sensitive or impulsive, poor self-control of behavior, mood swings, prone to the problem of hitting themselves. Second, there may be frustration, stress and other psychosocial factors caused by a bad defense, with their own hitting themselves this kind of aggressive behavior to relieve pressure, and even serious time will appear negative thoughts and behavior. Third, there may be psychological diseases caused by, such as anxiety, depression, these psychological diseases are easy to make people irritable and irritable, because of trivial arguments with people and even self-inflicted injuries and so on.