Objective The objective of this study was to explore the association between periodontitis and systemic lupus erythematosus (SLE). Methods To identify eligible studies, the PubMed, EMBASE and Web of Science databases were searched from inception to 19 September 2019. Associations of periodontitis, and other periodontal parameters, with SLE were assessed. Results Ten studies involving 80,633 subjects were included in this meta-analysis. Pooled data showed a significant association between periodontitis and SLE (odds ratio=5.32, 95% confidence interval (CI) 1.69–16.78, p = 0.004). In addition, SLE patients had a higher prevalence of bleeding on probing (mean difference = 0.03, 95% CI 0.00–0.06, p = 0.02) and higher mean clinical attachment loss (mean difference = 0.69, 95% CI 0.39–1.00, p < 0.001). However, there were no significant differences between SLE and reference subjects in mean plaque index, gingival index, pocket depth or decayed, missing or filled teeth. Conclusions This study demonstrates a significant association between periodontitis and SLE, which indicates that avoidance of periodontitis by maintaining oral health may be a simple and economical way to prevent SLE.