ABSTRACT: Increasing evidences support that systemic inflammation-based prognostic scores, modified Glasgow Prognostic Score (mGPS), C-reactive Protein/Albumin (CRP/ALB), Albumin/Globulin (AGR), Prognostic Nutritional Index (PNI) and Advanced Lung cancer Inflammation index (ALI), are key determinants of patients' outcome in solid tumors. However, in small cell lung cancer (SCLC), there have been no direct comparisons of them. Thus, the aim of this study was to compare the prognostic value of these markers in SCLC, and select a most appropriative one. The patients with confirmed SCLC were screened between 2006 and 2011, and inflammation-based prognostic factors (mGPS, CRP/ALB, AGR, PNI, ALI) were examined. Kaplan-Meier and Cox regression analysis were performed to assess these inflammation-based prognostic scores associated with overall survival (OS). Subsequently, we compared the prognostic value of these inflammation-based prognostic scores using the area under the curve (AUC). In 451 patients, on univariate analysis, mGPS (P<0.001), CRP/ALB (P<0.001), AGR (P<0.001), PNI (P<0.001) and ALI (P<0.001) were the strongest predictors of OS. Further multivariate analysis confirmed mGPS (P<0.001), CRP/ALB (P=0.007), AGR (P=0.034) and PNI (P=0.026) as independent markers associated with OS. Further subgroup analysis revealed CRP/ALB was able to predict outcome in both limited (P=0.005) and extensive disease (P=0.013). The CRP/ALB had higher AUC values compared with other inflammation-based prognostic socres (0.566). The CRP/ALB was characterized as best, in comparison to other systemic inflammation-based prognostic scores, for its predictive power of SCLC patients' survival, and had the potential to be hierarchical factor in future clinical trials.