Background Several FDG PET/CT parameters have been utilized to evaluate the prognosis in malignant pleural mesothelioma (MPM). However, there are still controversial results due to the low incidence of MPM. Purpose To assess the prognostic value of 18F-FDG PET/CT in MPM. Material and Methods A systematic literature search was performed in PubMed, Embase, Medline, and The Cochrane Library to identify eligible studies from inception to 12 February 2020. The pooled hazard ratios (HRs) and 95% confidence intervals (CIs) of several variables, such as maximum standardized uptake value (SUVmax), the reduction of SUVmax after treatment (Delta SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG), and the reduction of TLG after treatment (Delta TLG), were calculated. Meta-regression with subsequent subgroup analyses were conducted to determine the heterogeneity of cutoff values, treatment regimen, study design, uptake time, and scanners across various studies. Results In total, 19 eligible studies including 1819 patients were enrolled in the meta-analysis. The univariate analysis showed that the pooled HRs (95% CI) of SUVmax, Delta SUVmax, MTV, TLG, and Delta TLG were 1.29 (1.16-1.42), 1.12 (1.05-1.19), 1.15 (1.00-1.33), 1.47 (1.23-1.76), and 1.27 (1.12-1.45), respectively. The multivariate analysis showed that the pooled HRs (95% CI) of SUVmax, Delta SUVmax, MTV, and TLG for overall survival (OS) were 1.20 (1.08-1.33), 1.10 (1.02-1.19), 0.95 (0.81-1.11), and 1.13 (1.08-1.18), respectively. Conclusion SUVmax, Delta SUVmax, TLG, and Delta TLG are significant prognostic indicators for OS, while more clinical studies are needed to confirm the prognostic value of MTV in MPM.