Zhang Jinyue is a famous medical doctor in Ming Dynasty, which has been introduced before, so we will not repeat it here. Today, we will talk about how he understood insomnia in his treatise “The Complete Book of Jinyue”, so that we can discuss and learn together with fellow doctors. Insomnia is known as “sleeplessness” in ancient times, and Zhang Jingyue has discussed the causes and mechanisms of insomnia, as well as the treatment and prescriptions in his “Sleeplessness” chapter. The following is a detailed explanation. It is said in the book that the treatment of insomnia can be summarized by the word “evil and positive”, “Sleep is based on Yin, and God is its master, and when God is at ease, he sleeps; when God is restless, he does not sleep”. Why is it restless? There are two reasons: “One is due to the disturbance of evil qi, and the other is due to the deficiency of Ying qi.” There are causes of sleeplessness caused by typhoid, wind, and malaria; there are pathological products such as phlegm, fire, cold, and water; there are diet, emotion, thought, labor, fear, and doubt, and there is no cause of insomnia, in general, it belongs to the deficiency of its yin, essence, and blood; yin and yang do not feel each other, and the mind has restlessness in its room, then it becomes insomnia. Later Zhang Jinyue proposed that “drinking strong tea is sleepless, the heart has something also sleepless”, so why does strong tea lead to sleeplessness? The author said, the Wei Qi into the Yin is sleep, strong tea to the nature of Yin cold, large system Yuan Yang, Yang for Yin suppression, not into the Yin, it is caused by sleeplessness. The heart is disturbed by troubles, the heart and mind delusional restlessness is sleeplessness. To summarize Zhang’s discussion of the causes and mechanisms of insomnia, we can know that: the cause of insomnia is external sensation, diet, anger, thought and fatigue. The pathogenesis of insomnia is due to external disturbance and deficiency of Ying Qi. In addition, the author explains why drinking strong tea and heart problems can cause insomnia. This gives us a lot of ideas for treating insomnia, such as treating primary diseases such as cold and malaria, and also paying attention to lifestyle control, i.e., diet regulation, not drinking strong tea, maintaining emotional optimism, relaxing life stress, etc.