Aim of the study: to prove the presence of neurotropic viruses in glioblastoma and to determine their potential effect on the outcome of overall survival and progression-free survival. Definition of prognostic factors in the treatment of glioblastoma was set as a secondary objective of this study. Subjects and methods: a group of sixty-three patients with glioblastoma was retrospectively analyzed during the time period of five years, between January 1, 2012 and December 31, 2017. In all patients, glioblastoma was pathohistologically confirmed, thus establishing a homogeneous group of subjects. Re-evaluation using hemalaun-eosin staining and subsequent immunohistochemical staining was performed on archival samples of tumor tissue. Results: a positive outcome was obtained in eleven samples for the presence of NTV in glioblastoma tissue, which was evaluated by the IRS method. Statistical processing using the SPSS system did not prove a statistically significant outcome of OS and PFS in the group of patients with proven NTV. Statistically significant factors for overall survival ware confirmed for predictive factors including preoperative ECOG assessment (p = 0.03), postoperative Karnofsky assessment (p = 0.002), radiotherapy (p = 0.001), and chemotherapy (p = 0.009). Statistically significant value for progression-free survival was related to patients' age value (p = 0.03), postoperative Karnofsky assessment (p = 0.037), postoperative radiotherapy (p = 0.002), chemotherapy (p = 0.02) and the time interval between the surgery and oncological treatment (p = 0.049). Conclusion: despite the proven presence of NTV in glioblastoma tumor tissue, the influence of the virus on the onset and development of the disease has not been proven. The prognostic factors defined by this study have shown a significant impact on OS and PFS. Although the results are promising, further evaluation of these factors by modifying the research methods and study design is necessary.