Epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKIs) have become the preferred therapy as first-line treatment of non-small cell lung cancer patients harboring sensitizing EGFR mutations. However, the prognostic indicators are limited. The present study aimed to assess the prognostic value of immune-inflammation factors, fibrinogen-albumin ratio index (FARI), neutrophil to lymphocyte ratio (NLR), and platelet to lymphocyte ratio (PLR) in EGFR-Mutant lung adenocarcinoma patients receiving first-generation EGFR-TKIs treatment.194 patients were included in this retrospective analysis. FARI was calculated as fibrinogen / albumin. Receiver operating characteristic curve was used to evaluate the optimal cut-off value for FARI, NLR, and PLR to progression free survival (PFS). Univariate and multivariate survival analysis were performed to identify factors correlated with PFS and overall survival (OS).Applying cut-offs of ≥0.08 (FARI), ≥3.28 (NLR), and ≥273.85 (PLR), higher FARI or NLR was associated with worse Eastern Cooperative Oncology Group performance status (ECOG PS) (P = .018, .002, respectively), and there were more males in high NLR group (P = .043). In univariate analysis, ECOG PS status, NLR, PLR, and FARI were significantly associated with PFS (P = .017, .004, <.001, .001, respectively) as well as OS (P < .001, = .001, .002, .023, respectively). In multivariate analysis, PLR (hazard ratios [HR] 1.692; 95% CI 1.054-2.715; P = .029) and FARI (HR 1.496; 95% CI 1.031-2.172; P = .034) were independent prognostic factors for PFS. While only ECOG PS status (HR 2.052; 95% CI 1.272-3.310; P = .003) was independently correlated with OS.FARI is independently associated with PFS in EGFR-Mutant lung adenocarcinoma patients receiving first-line EGFR-TKIs treatment.