The clinical manifestations of children with ADHD, especially the milder ones, can easily be confused with the demeanor of normal naughty children. In terms of children’s self-control, three types of children can be seen in any elementary school class: those who are disciplined and study hard in class, and who, in addition to doing well on their own, are able to supervise and remind other students. Such children are only a minority in the class. One category is those who are able to restrain their behavior in class and pay attention to the lecture. They may be distracted or make small movements when they listen for too long or are not interested in what the teacher is teaching, but they can correct them immediately after the teacher reminds them. This is the majority of students in every class. Another group of children with ADHD are those who are active, capricious, impulsive, and have difficulty controlling themselves. These children are also a minority in the class. This situation of few at both ends and many in the middle constitutes a normal distribution of self-control for elementary school students. As far as self-control is concerned, there is no qualitative difference between ADHD and normal naughty children, only a difference in quantity and frequency. Therefore, it is easy to be confused in the diagnosis. In general, the following points can be used to make a preliminary distinction: 1. The activities of children with ADHD are often purposeless, with no end in sight and constantly changing patterns of movement. The normal naughty children’s hyperactivity is often motivated by some kind of purpose, such as borrowing a rubber from the next child, but also whispered “thank you”, the teacher asked a question in order to show themselves, without raising their hands to answer first, etc. 2, hyperactive children’s behavior often regardless of the occasion, regardless of the consequences, can not be self-control. The normal naughty children, by the time and place of some restrictions will be restrained. The company’s main goal is to provide a comprehensive range of products and services to the public. In contrast, normal naughty children will improve after the inspiration and education, and only after a long period of time will they regain. In addition, children with ADHD have symptoms such as impulsivity, agitation, abnormal behavior, and learning difficulties. It is not difficult to distinguish ADHD from normal children through diagnostic tools such as scale scores and test analysis.