Dreaming in light sleep is usually a normal physiological phenomenon. The sleep cycle of a person includes light sleep as well as deep sleep, and after entering sleep, a person will alternate between deep sleep and light sleep and repeat the process. The cerebral cortex is more active during light sleep, so dreams can occur. Light sleep dreaming may be related to daily life style, daytime work pressure, excessive tension and fatigue, mental stress, during the light sleep period, the subconscious mind may have thoughts about the daytime events, thus producing dreams. Drinking coffee or strong tea and other beverages that enhance one’s excitability before going to bed, or watching electronic products or horror movies before going to bed to excite the brain center can also cause shallow sleep and more dreams. If frequent dreams or nightmares, consider the possibility of neurasthenia, may be related to irregular work and rest, stay up late and cold, lack of exercise, emotional anxiety, work stress. It is recommended to relax, maintain emotional stability, reduce the causes of dreaming, and improve the quality of sleep.