Data sources Cochrane Central Register of Controlled Trials (CENTRAL), Medline (Ovid), Embase, Web of Science, Latin American & Caribbean Health Sciences Literature (LILACS) and SIGLE database.Study selection Randomised controlled trials (RCTs), controlled clinical trials (CCTs), cohort studies, case-control studies and cross-sectional studies.Data extraction and synthesis Two reviewers screened papers independently and assessed the risk of bias. Data categorised based on the study design. The primary outcome was the odds ratio (OR)/relative risk (RR) and confidence interval (CI) for hypertension in individuals with periodontitis.Results Diagnoses of moderate-to-severe (OR = 1.22; 95% CI: 1.10-1.35) and severe periodontitis (OR = 1.49; 95% CI: 1.09-2.05) were associated with hypertension. Diagnosis of periodontitis increased odds of occurring hypertension (OR = 1.68; 95% CI: 0.85-3.35). Patients with periodontitis exhibited higher mean systolic (weighted mean difference [WMD] of 4.49 mmHg; 95% CI: 2.88-6.11) and diastolic blood pressures (2.03 mmHg; 95% CI: 1.25-2.81). There was inconclusive evidence that periodontal therapy reduces blood pressure (3-12.5 mmHg of systolic and 0-10 mmHg of diastolic blood pressures).Conclusions Periodontitis could be associated with increased risk of hypertension. Further, the management of periodontitis could impact on the management of hypertension. However, there is still a need for more high-quality research.