Amyloid-beta plaques, tau tangles, and impaired memory are some of the hallmarks of Alzheimer’s disease (AD), an irreversible neurological illness. The gut-brain axis plays a crucial role in neurodegeneration; in addition, latest studies have revealed a strong connection involving gut microbial imbalances as well as AD pathophysiology. The idea that microbial disequilibrium inside the gut can affect the functioning of the nervous system through a variety of mechanisms, such as immunological induction, systemic allergic reactions, microbiological metabolite signaling, and interruption of the blood-brain barrier, is examined in this chapter. Modifications in gut microbial composition—marked by decreased beneficial taxa and increased pro-inflammatory species—are increasingly recognized in AD patients and animal models. Through molecules including short-chain fatty acids, lipopolysaccharides, and tryptophan derivatives, these microbial changes can impact neuroinflammatory activities along with amyloid deposits pathology. The chapter critically examines the mechanistic underpinnings of gut-brain interactions; the impact of aging, diet, and environmental factors on microbiome integrity; and the potential of microbiota-targeted therapies, including probiotics, dietary interventions, and fecal microbiota transplantation. This chapter provides new insights for early identification and engagement in the treatment of neurodegenerative illnesses by combining clinical along with experimental findings to demonstrate the medical benefits of altering the gut microbiota in AD.