Cancer-related insomnia is one of the common complications in clinical oncology patients,can appear after tu-morigenesis and development and anti-tumor therapy,which often affects the quality of life of oncology patients,the efficacy of oncology treatment and the prognosis of oncology diseases.For its treatment,Western medicine often relies drugs such as benzodiazepines,and long-term use of which has problems such as dependence,addiction and poor efficacy,so it is necessary to seek the help of traditional Chinese medicine.Cancer-related insomnia belongs to the category of"insomnia"in Chinese medicine.Combined with the theory of"liver storing blood and blood shed soul"in the basic theory of Chinese medicine,it is believed that"insomnia"is closely related to the liver and its etiology and pathogenesis lies in"liver does not store the soul".In this paper,we discuss the etiology and pathogenesis of insomnia from the perspective of"five viscera storing five spirit","spirit with soul",and analyzes that"liver storing soul"is closely related to Cancer-related insomnia.It also introduces the clinical efficacy of treating Cancer-related insomnia with Xiaobugan Decoction from the perspective of"liver",thus providing ideas for the clinical application of the theory of"liver storing soul"in the treatment of Cancer-related insomnia.