Some people often sleep poorly because they dream a lot. They worry that dreaming a lot will hurt their brain and want to dream less. Dreaming during sleep is a physiological phenomenon. A normal person can dream 4-6 times a night, adding up to no more than two hours in total, which will neither hurt the brain nor affect health. The ancient interpretation of dreams, “daytime dreams, nighttime dreams”, still seems to have some meaning nowadays. Most people have the experience that what they think about during the day, they dream about at night. Freud, the father of psychoanalysis, believed that dreams are the manifestation of the subconscious mind. As science has developed, more and more has been learned about dreams. Simply put, dreams are caused by the local brain tissues that have not yet completely stopped their excitatory activity while a person is sleeping, thus causing representational activity. Some “traces” of the stimuli in the environment are left in the cells of the human cerebral cortex. We know that whether external or internal stimuli are transmitted to the brain, they leave traces in the brain, whether they are seen, heard, smelled, touched, thought or done. Our work and life during the day depend on the activity of this trace. During the day, we consciously choose to use these “traces”. During sleep, these “traces” are active and constitute a variety of dreams. Some people feel that they dream all night long, which is related to their personalities, emotions, social experiences and cultural backgrounds. Some people, for example, care about their own feelings, sleep more superficial, easy to wake up and can clearly remember the dream; depressed people often sleep restlessly, wake up from the dream, feel dreamy; others, think that dreaming is a sign of bad things happen, so that the emotional tension is excessive, more likely to wake up from sleep, feel dreamy. To treat dreaming correctly, adjust it psychologically, or treat it under the guidance of a doctor, so that the biological rhythm of excitation and inhibition of the brain becomes balanced and harmonious, eliminating tension and making it sleep well.