Aging is increasing all over the world, and the health problems in the elderly, including dementia, are becoming increasingly prominent, with an increasing number of patients with Alzheimer′s disease (AD). AD essentially, is a condition of neuroinflammation, and is closely related to sleep and immune function, while, insomnia can induce an inflammatory response, destroy the abundance and diversity of intestinal flora, and ultimately promote the development of the disease. Since the pathogenesis of AD is still unclear, the therapeutic effect of Western medicine is relatively disappointing. Here, based on the consistency and correlation between the “Cerebrointestinal axis” theory and the concept of “all diseases are born from spleen and stomach failure” in Traditional Chinese Medicine, we discuss to “Cure from the Spleen” for insomnia so as to reshape the gut microbiota and thus be beneficial to prevent and treat AD.