ObjectiveHelicobacter pylori (H. pylori) infection affects approximately 50% of the global population. The predominant route of H. pylori transmission is through the oral pathway, making the oral cavity highly significant in its infection. This review focuses on the relationship between H. pylori and oral diseases, the influence of H. pylori infection on the oral microbiota, and the potential mechanisms involving certain oral pathogens.MethodTo identify relevant studies, we conducted searches in PubMed, Google Scholar using keywords such as "Helicobacter pylori," "oral diseases, " "oral microorganisms, " without any date restrictions. The retrieved publications were subject to a review.ResultsH. pylori infection is positively correlated with the occurrence of various oral diseases, such as dental caries, periodontitis, and oral lichen planus. H. pylori may affect the oral microbiota through various mechanisms, and there exists an interactive relationship between H. pylori and oral bacteria, including Streptococcus, Porphyromonas gingivalis (P. gingivalis), and Candida albicans (C. albicans).ConclusionsH. pylori infection has a close relationship with certain oral diseases. H. pylori modulates oral microflora diversity and structure, while eradication therapy and medications have varying impacts on oral microbiota.