The causes of daytime dreaming include: psychological factors, physiological factors, environmental factors, and somatic factors. Psychological factors: If you are always thinking about something during the day, this thing will also recur during sleep; in addition, excessive psychological burden can also lead to excessive dreaming, such as mental tension before bedtime, worry about excessive dreaming symptoms, etc.; physiological factors: too full or too hungry before bedtime, daily smoking or drinking a lot of alcohol, drinking stimulating foods such as coffee, tea or functional drinks, intense exercise before bedtime which leads to mental arousal Environmental factors: poor sleep environment or change of sleep environment may lead to unrealistic sleep, stimulation of various environmental factors outside the body during sleep, such as light, temperature, sound, etc.; somatic factors: neurological diseases, respiratory diseases, drug factors, etc. may also lead to excessive dreaming. In short, dreaming is a normal physiological activity of human, caused by the internal and external stimuli and the external stimuli received by the brain during the day in the brain image activity. If dreaming affects the quality of sleep, we should look for the causes from the above factors and correct them in time. We must keep our mood relaxed, avoid emotional irritability, arrange our rest and rest time reasonably, and make adjustments under the guidance of clinicians.