The significance of various factors that may be predictors of a favorable course of the disease is discussed in the literature. This work is the first part of analysis of prognostically significant factors positively affecting overall survival of glioblastoma patients. In our series, the predictors of a favorable prognosis for long-living patients with the verified diagnosis of glioblastoma were as follows: young age, the supratentorial location of the tumor, a high Karnofsky score before surgery, and tumor resection. In our series, we used immunohistochemical tests and found no prognostic significance of the IDH1 gene mutation; further analysis will require application of direct sequencing. We plan to study other morphological and molecular genetic features of tumors, which explain prolonged survival of glioblastoma patients, as well as the role of various types of combined chemoradiation treatment.