Abstract:As one of the key pathogenic bacteria of periodontitis, Porphyromonas gingivalis is closely associated with the occurrence and development of Alzheimer’s disease (AD). P. gingivalis promotes the development of AD by secreting various virulence factors, such as lipopolysaccharides (LPS), gingipains, and outer membrane vesicles (OMVs). These virulence factors are capable of inducing systemic inflammation, β-amyloid (Aβ) deposition, Tau protein phosphorylation, neurotoxicity, and damage to the blood-brain barrier (BBB), playing a role in the pathogenesis of AD. This review summarizes the association between P. gingivalis and AD, aiming to provide a new target for the prevention and treatment of AD.