Objectives: Aims of this SR were to assess the association of Periodontitis (PD) with Chronic Kidney Disease (CKD) and with different CKD stages. Materials and methods: MEDLINE, Cochrane Central Register of Trials and EMBASE, up to April 4, 2021 were searched. RCTs, prospective and retrospective cohort studies, case–control studies and cross‐sectional studies were considered. JBI's Critical Appraisal Tool for risk of bias assessment was used. The risk of PD was calculated using the Mantel–Haenszel odds ratios (MH‐OR); weighted mean difference for clinical attachment level (CAL) and periodontal probing depth (PPD) were also evaluated. Results: Out of 1949 titles screened, 142 full texts were evaluated and 17 studies were included. CKD was associated to higher risk of PD (MH‐OR = 2.36, [95% C.I. 1.25, 4.44]; p = 0.008), higher mean CAL (WMD = 0.41 mm [95% C.I. 0.22, 0.60]; p < 0.0001) and mean PPD (WMD = 0.25 mm [95% C.I. 0.03, 0.47]; p = 0.02) compared to healthy individuals. Severe CKD (stages 4–5 vs 2–3) resulted at higher risk of PD (MH‐OR = 2.21, [95% C.I. 1.07, 4.54]; p = 0.03). Heterogeneity and risk of bias were high. Conclusions: An association between PD and CKD was found. It could be appropriate to consider PD a frequent CKD comorbidity. [ABSTRACT FROM AUTHOR]