The diagnosis of dreamwalking disorder can usually be understood and determined through the patient’s medical history. Dreamwalking disorder is apparently a mutated state of consciousness in which the patient loses contact with his surroundings and the patient seems to live in a private world. The patient is sometimes very agitated and may even speak a great deal of nonsense, making it difficult for the person next to him to understand what he is saying. The patient seems to be engaged in a very meaningful activity. This activity is often a symbolic reenactment of the patient’s repressed painful experience. The patient knows nothing about the dreamwalking disorder when it is over. Diagnostic criteria of DSM-III: The diagnostic criteria in the Diagnostic and Statistical Manual of Mental Disorders DSM-III are the most recent definition of somnambulism in psychology and include the following five points: 1. Frequent sleep-waking and walking behavior, usually occurring in the initial third of the major sleep stages. 2. When sleep walking disorder is present, the patient has a dull facial expression and is largely unresponsive to stimuli from others, and the sleep walker is difficult to be forcibly awakened. 3.When awake (either at the end of the somnambulism or in the next morning) the patient mostly forgets everything that happened in the somnambulism. 4. When waking up from the dreamwalking state within a few minutes, the patient’s mental activity and behavior are not impaired (although the patient has confusion and disorientation in the initial moment of waking up). 5. No organic factors, such as epilepsy, are involved in the onset and progression of the sleep walking disorder. What is the first symptom, what are the characteristics of the form of onset, whether there is a stressful life event, what are the characteristics of the course of the illness, and whether it is persistent. 2. What is the behavior during the attack, what is the attention and responsiveness, and whether the patient can return to bed quietly by himself or guided by others. 3. Whether the patient can recall what happened after waking up. 4. The presence of family members with sleep walking disorder, night terrors or enuresis in the family. 5. Whether the patient’s social function is impaired. 6.Whether the patient has suffered from mental disorder before, whether he/she suffers from other physical diseases, and whether there is any possibility of drug triggering. 7. What are the personality characteristics of the patient and whether there are corresponding psychological factors.