Background: Sepsis continues to carry a high rate of mortality, which makes effective and simple evaluation methods for predicting the prognosis of septic patients especially important. In this study, we retrospectively analyzed the relationships between three scoring systems including Sequential Organ Failure Assessment (SOFA) score, Quick SOFA (qSOFA) score, and Logistic Organ Dysfunction System (LODS) score and the prognoses of septic patients. Methods: The baseline data, SOFA score, qSOFA score, LODS score, 28-day prognosis, and 90-day prognosis of patients who met the diagnostic criteria of sepsis were retrieved from the Medical Information Mart for Intensive Care III (MIMIC-III) database. Receiver operating characteristic (ROC) curves were drawn for various indicators, and comparisons were drawn between the areas under the ROC curves (AUC) of the different scoring systems. Results: The 28-day AUC was 0.661 (0.652, 0.670) for SOFA, 0.558 (0.548, 0.568) for qSOFA, and 0.668 (0.658, 0.677) for LODS; AUC-qSOFA vs. AUC-LODS was 0.103 (0.087, 0.120) (P<0.001), and AUC-qSOFA vs. AUC-LODS was 0.110 (0.094, 0.125) (P<0.001). The 90-day AUC was 0.630 (0.621, 0.640) for SOFA, 0.551 (0.541, 0.560) for qSOFA, and 0.644 (0.635, 0.653) for LODS; AUC-SOFA vs. AUC-qSOFA was 0.079 (0.065, 0.094) (P<0.001), and AUC-qSOFA vs. AUC-LODS was 0.093 (0.079, 0.107) (P<0.001). Conclusions: SOFA score, qSOFA score, and LODS score can all be used to predict the prognosis of septic patients. LODS score and SOFA score have higher accuracy than qSOFA score; however, qSOFA is simpler to use, making it a more suitable tool in an emergency setting.