Context: The prognostic criteria for early-stage nonsmall cell lung cancer (NSCLC) wait to be explored. Aim: In this study, our aim was to evaluate the prognostic significance of the positron emission tomography/computed tomography (PET/CT) maximum standardized uptake value (SUVmax) value of the primary tumor in patients with a diagnosis of early-stage NSCLC who received surgical treatment. Settings and Design: This was a multicenter retrospective design. Materials and Methods: Patients who had been diagnosed with early-stage NSCLC and who underwent surgery for the condition were included in this study. The preoperative fluorodeoxyglucose (18F-FDG) PET/CT results of the patients were retrospectively accessed from their medical files. The disease-free survival (DFS) rates of patients who had SUVmax values above and below the determined cutoff value were compared. Statistical Analysis Used: SPSS version 22 and Kaplan-Meier method were used for statistical analysis. Results: A total of 92 patients were included in the study. The median age of the patients was 60 years (range: 36-79). The determined cutoff SUVmax value of the primary tumor was 13.6. A comparison of the DFS rates of the patients with an SUVmax value above and below 13.6 revealed a significant difference in patients with Stage I (22.9 months vs. 50.3 months; P = 0.02) and Stage II (28 months vs. 40.4 months; P = 0.04), Stage I + II (43.5 months vs. 26.1 months; P = 0,02), and Stage IIIA (14.7 months vs. 13.6 months; P = 0.92) NSCLC. Conclusions: We found that in early-stage NSCLC patients, the SUVmax value of the primary mass in 18F FDG PET/CT was a prognostic indicator for the DFS rates.