Objective To mine the medication rule of Chinese medicine treating insomnia by analyzing medical records of insomnia in ancient medical books. Methods The medical records with insomnia as the main symptom were reviewed in Unihan Ancient Books Database by combination of computer retrieval and manual retrieval. A database was built by extracting the information of prescription names and herbs of included medical records. The frequency statistics of herb used alone

couplet herbs

3-herb-combination groups and high frequency herbs classification were made. Results Totally

647 prescriptions were included

325 herbs used. There were 20 herbs with the use frequency larger than 10%. The herbs with top use frequency were Gancao [Radix Glycyrrhizae]（ 43. 74%）

Renshen [Radix Ginseng]（ 38. 79%） and Fuling [Poria]（ 35. 24%）. There were 18 couplet herbs with the use frequency larger than 10%. The couplet herbs with top use frequency were Gancao-Renshen（ 22. 10%）

Suanzaoren[Semen Ziziphi Spinosae]-Renshen（ 20. 25%） and Gancao-Fuling（ 19. 78%）. There were 5 3-herb-combination groups with the use frequency larger than 10%. The groups with top use frequency were Gancao-Shengjiang [Rhizoma Zingiberis Recens]-Renshen（ 11. 13%）

Gancao-Fuling-Renshen（ 10. 97%） and Suanzaoren-Fuling-Renshen（ 10. 97%）. Among 55 herbs with high frequency

herbs of replenishing deficiency got the top use frequency（ 1316

26. 79%）

the second were herbs of tranquillization（ 573

11. 67%） and clearing heat（ 503

10. 24%）. Conclusion In order to treat insomnia

Chinese medicine physicians mostly used herbs for replenishing deficiency; these herbs mostly influenced the heart and spleen channels. The deficiency of heart and spleen mainly manifested as blood deficiency. Thus the authors thought that treating insomnia might focus on nourish heart-spleen and replenish Qi-blood.