To compare 5 published scoring systems (Fournier gangrene severity index [FGSI], Uludag FGSI [UFGSI], age-adjusted Charlson Comorbidity Index [ACCI] and the Quick Sequential Organ Failure Assessment (qSOFA) and the Laboratory Risk Indicator for Necrotizing fasciitis (LRINEC) scores and to evaluate risk factors for outcome prediction in patients with Fournier gangrene (FG). Between 2010 and 2024, 311 patients were included in the study. The data of 276 survivors and 55 non-survivors were compared. Univariate and multivariate analyses were performed to determine which of the 5 scoring systems calculated according to demographic, laboratory and clinical data predicted mortality better. In addition, a cut-off value for these scoring systems was determined by ROC analysis. The mortality rate was 17.6% in FG patients. In all 5 scoring systems, univariate analyses showed higher values in non-survivor patients, while UFGSI and FGSI scoring systems were superior to other scoring systems in multivariate analyses (p < 0.001). ROC analysis using mortality-based sensitivity and specificity revealed that the optimal cut-off values for FGSI, UFGSI, ACCI, SOFA and LRINEC should be equal to or higher than 10, 12, 4, 2 and 8, respectively. UFGSI and FGSI scores had the highest AUC values among all scores. This was followed by ACCI, qSOFAand LRINEC. For a UFGSI score ≥ 12, the sensitivity was 84%, specificity 97%, PPV 85% and NPV 97%. Among the scoring systems used to predict mortality, UFGSI was the most accurate, while LRINEC was the least accurate.