AIM: This study was done to assess the survival of patients with glioblastoma multiforme (GBM) and to identify factors that can affect patient survival. MATERIALS AND METHODS: From January 2015 to December 2019, 55 patients with histopathologically confirmed GBM and received adjuvant radiation/chemoradiation in our department were retrospectively analyzed. RESULTS: The median overall survival (OS) for entire cohort was 13 months and 1-year OS and 2-year OS rate were 52.7% and 3.6% with the mean follow-up period was 12 months. In univariate analysis, age (≤50 years vs. >50 years, p = 0.02), performance status (≥90 vs. 70–80 vs. <70, p < 0.001), radiation therapy oncology group recursive partitioning analysis (RTOG-RPA) classification (Class III vs. Class IV vs. Class V-VI, p < 0.001), parietal lobes tumor site (vs. others, p = 0.02), residual tumor volume (≤20.4 cm3 vs. >20.4 cm3, p = 0.001), and time to initiate adjuvant therapy (<4 weeks vs. 4-6 weeks vs. >6 weeks, p = 0.01) were significantly affect OS. In multivariate analysis, RTOG-RPA classification and involvement of parietal lobes were independent prognostic factors for OS. CONCLUSIONS: RTOG-RPA classification that consisted of age and performance status is an independent prognostic factor for the clinical outcome of GBM. Besides this well-known factor, we also identified the involvement of parietal lobe gives a strong negative influence on survival of GBM patients. © 2021 Sudibio Sudibio, Jellyca Anton, Handoko Handoko, Tiara Bunga Mayang Permata, Henry Kodrat, Endang Nuryadi, Henry Riyanto Sofyan, Rahmad Mulyadi, Renindra Ananda Aman, Soehartati Gondhowiardjo.