Insomnia is the end result of many complex factors, including changes in various factors such as physiological, psychological and environmental factors, as well as medications, neuropsychiatric and physical disorders, mainly manifested as difficulty in falling asleep, difficulty in waking up easily at night and falling asleep again, and less time to maintain sleep. The common causes of insomnia are as follows: psychological factors: for example, perfectionists, introverts or people with anxiety characteristics; in addition, a change in the sleep environment or some unexpected events around the mood fluctuations, the intensity of work or life stress; adult women with the gradual increase in age insomnia is also gradually higher, while in childhood there is no gender distribution differences. Contemporary social competition is increasingly fierce, work and life pressure is increasing, coupled with a variety of interests in life, complex interpersonal relationships, so that many psychologically vulnerable people are physically and mentally exhausted, the mind has been in a state of tension, can not relax. Excessive tension, busy, heavy heart, can not be released, is the most common cause of insomnia. Environmental factors: changes in the sleep environment can cause a decline in sleep quality, such as travel by car, boat or airplane, due to the surrounding noise, bumps in travel, and concerns about travel safety, making it difficult for some people to fall asleep, or to ensure sleep quality. Some people will have the so-called “bed recognition”, only at home or a fixed place to sleep peacefully, otherwise they can not sleep, or even insomnia throughout the night. Obviously, it is difficult for them to get a good sleep when they travel, visit friends and relatives or have other business to leave home. Past medical history: the incidence of insomnia in those with a family history of insomnia is three times higher than that in those without a family history; certain physical and mental disorders, such as neurasthenia, anxiety disorder, depression, obsessive-compulsive disorder, mania, schizophrenia and certain personality disorders. For example, depressive disorder mainly manifests as early awakening, generally waking up 2-3h earlier than usual, not being able to fall asleep again after early awakening, or having difficulty falling asleep, tossing and turning, and feeling sleepless even after falling asleep; patients with mania have less sleep or no sleep due to day and night excitement; patients with anxiety disorder also have difficulty falling asleep and sleepless due to excessive mental tension and increased nervous excitability. Drug influence: Some insomnia is caused by drugs, that is, pharmacogenic insomnia. Drugs that increase nerve excitement, pacifiers, cardiac drugs, diuretics, and antihypertensive drugs can have side effects that cause insomnia. Therefore, insomnia is a subjective experience of insomniacs who are not satisfied with the quality of sleep, sleep time and sleep efficiency. Long-term insomnia will affect the normal function of the brain and body and should be treated early.