Childhood ADHD, also known as attention deficit hyperactivity disorder (ADHD), is a common psychobehavioral disorder syndrome of childhood. Psychologists refer to this problem as “psychobehavioral deviation” and psychiatrists consider it to be a borderline psychiatric disorder. In society, especially elementary school teachers and parents tend to call hyperactive or inattentive students and children “childhood ADHD”, which is partly true and partly misunderstood. So, what is ADHD in children? International organizations have a clear definition of ADHD in children. Attention deficit: The child’s attention is inattentive, because passive attention is better than active attention, so attention is easily attracted to other things around the past, in class when the mind deserted, do things in two minds, tiger head and snake tail, there is no end, homework to do and stop. They know they want to change, but they can’t control and regulate themselves. This is one of the most basic features of ADHD in children; 2. hyperactivity: children with excessive activity, hands and feet in class, making small movements, provoking people, and not abiding by classroom discipline. Children with ADHD often break toys and even engage in dangerous behaviors, and cannot be quiet even when they want to be; 3. For example, the number symbol “+” is written as “-“, the phonetic alphabet is confused, etc.; 5. Normal intelligence: learning performance fluctuates greatly, and even appears to have learning difficulties, sometimes failing exams. The above points are the internal characteristics of ADHD in children. However, it must be emphasized that whether a child with these conditions can be diagnosed with ADHD requires a diagnosis and differential diagnosis by a physician before a decision can be made. There are many disorders that have similar clinical manifestations to ADHD in children.