Background: Complicated intra-abdominal infection is an infection that requires more attention associated with a poor prognosis and a fairly high mortality rate and has the second highest mortality rate in the Intensive Care Unit (ICU). This study was to assess the relationship between the extent of peritonitis, abdominal fluid characteristics, and organ source of infection with mortality in patients with complicated intra-abdominal infections. Methods: Meta-analytical study, retrospective cohort method, data taken from online literature search. Analyzes followed PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and used Review Manager 5.4 software. Results: There were 9 literatures that matched the inclusion criteria. The relationship between the extent of peritonitis and mortality analyzed showed an odds ratio of 3.08 (95% CI 1.77-5.38), the relationship between abdominal fluid characteristics at the time of surgery and the analyzed mortality showed an odds ratio of 7.65 (95% CI 1.06-55.06), and the relationship of the source of infection from organs to mortality showed an odds ratio of 2.54 (95% CI 1.77-3.63). Conclusion: There is a relationship between the extent of peritonitis and mortality in the incidence of complicated intra-abdominal infections, there is a relationship between the characteristics of abdominal fluid and mortality in the incidence of complicated intra-abdominal infections, and there is a relationship between the source of organ infection and mortality in the incidence of complicated intra-abdominal infections.