Objective: A systematic review including meta-analysis was conducted to test the null hypothesis of no difference between immediate loading and delayed loading fixed implant-supported restoration for completely edentulous arch in terms of implant failure rates and marginal bone resorption against the alternative hypothesis of a difference. Materials and methods: An electronic search was undertaken in January 2019. Inclusion criteria including clinical human studies, either randomized or not, studies comparing success, survival, or failure rates of immediately loaded implants with fixed restoration to delayed loaded implants on edentulous jaw, patients who were examined clinically at follow up visits for at least 12 months. The estimates of relative effect were reported in risk ratio (RR) and mean difference (MD) in millimeters. Results:1355 studies were initially identified and 11 studies were finally included for meta-analysis. The results showed that there was no statistically significant difference between immediate loading and delayed loading (P Conclusion: The differences in loading protocol between immediate loading and delayed loading of full arch implant-supported fixed prosthesis might not affect the failure rates of dental implants and there is no significant effect on marginal bone resorption.