Insomnia is the most frequent clinical disease and accompanying symptom of common diseases.The number of cases of insomnia is increasing year by year.Insomnia has become an increasingly important problem affecting people's physical and mental health.Traditional Chinese medicine has the advantages of assuring curative effect and limited side effects in the treatment of insomnia.The syndrome differentiation of insomnia is divided into deficiency syndrome and excess syndrome,which are mostly related to the heart,liver,spleen,kidney,etc.Deficiency syndromes are more common in heart,liver and blood deficiency,heart and spleen deficiency,Yin deficiency and excess fire,heart and kidney incompatibility,heart and gall qi deficiency.Excess syndromes include syndrome of hyperactive heart and liver fire,internal obstruction of blood stasis,internal disturbance of phlegm-heat,and stomach-energy stasis due to improper diet.Clinical syndromes are more common with both deficiency and excess syndromes.This article sorts out the common prescriptions and medical syndromes of insomnia,especially the main syndromes of insomnia,such as having difficulties of falling asleep,awakening in the middle of the night,early awakening,excess dreams,shallow sleep,and daytime dysfunction.It's important to pay attention to the main symptoms.We should combine disease differentiation and syndrome differentiation to make it more accurate.This article also summarizes the prescriptions and medicine syndromes combining the cause and pathogenesis of insomnia,comorbid or secondary symptoms,patient physique type,modern pharmacological research,etc.