There were increasing studies on the association of periodontal diseases with coronary heart disease (CHD) in the recent 20 years. This article reviewed the evidence supporting the association between periodontal disease and CHD, the possible mechanisms explaining the association, and the possible effect of periodontal treatment on the risk of CHD. In general, it is suggested that periodontal disease especially, periodontitis is modestly associated with CHD. Besides there are some common risk factors, such as smoking, stress, elder age, male gender and low socioeconomic status, between these two diseases, long chronic periodontal infections by periodontal pathogens, the systemic acute-phase response and host immuno-inflammatory response to the exposures of periodontal infection appear to be the important mechanisms for connecting the periodontal disease and CHD. Periodontal treatment can decrease the infection of periodontal pathogens and therefore, reduce the systemic inflammatory burden. It was observed in some studies that periodontal treatment could reduce the serum inflammatory biomarkers such as C-reactive protein and improve endothelial function. Even though the studies on effect of periodontal interfere on CHD are still limited now, it appears hopeful that periodontal treatment could reduce the risk of CHD and therefore become one of the preventing strategies for CHD.