Our study aims to estimate the prevalence of surgical site infections (SSI) following open reduction and internal fixation (ORIF) for mandibular fractures and to determine the effect of potential moderators on it. A systematic literature search (Medline and Scopus databases) was conducted independently by two reviewers. The pooled prevalence with 95% confidence intervals was estimated. Quality assessment as well as outlier and influential analysis were performed. Additionally, subgroup and meta-regression analysis were conducted in order the effect of categorical and continuous variables on the estimated prevalence to be investigated. In total, seventy-five eligible studies (comprising a sum of 5825 participants) were included in this meta-analysis. The overall prevalence of SSI following ORIF for mandibular fractures was estimated as high as 4.2% (95% CI 3.0–5.6%) with significant heterogeneity between studies. One study was identified to be critically influential. In the subgroup analysis, the prevalence was 4.2% (95% CI 2.2–6.6%) among studies conducted in Europe, 4.3% (95% CI 3.1–5.6%) among studies conducted in Asia and higher among those conducted in America (7.3%) (95% CI 4.7–10.3%). It is important for healthcare professionals to be aware of the etiology of these infections, despite the relatively low rate of SSI in these procedures. However, further, well-designed prospective and retrospective studies need to be conducted in order this issue to be fully clarified.