Glioblastoma multiforme (GBM) is the most aggressive form of primary brain tumor, known for its rapid progression and poor prognosis. Standard treatment includes surgical removal of the tumor, radiotherapy, and chemotherapy. Despite intensive treatment, the median survival of patients is often less than 15 months. A multimodal approach, which combines different treatment methods, is considered crucial for improving outcomes in patients with GBM. Surgical removal of as much of the tumor as possible (maximal resection) is the first step, which can reduce tumor mass and facilitate further treatment. Postoperative radiotherapy with temozolomide (a chemotherapeutic agent) is the standard combination used to destroy remaining tumor cells. Advances in molecular biology have led to the development of immunotherapy, which shows promising results. Immunotherapy uses the patient's immune system to attack tumor cells. Numerous clinical studies are currently being conducted on this topic, such as humanized antibodies, peptide vaccines, dendritic cell therapy, and many others. Integration of personalized medicine, based on the genetic profile of the tumor, could further enhance treatment effectiveness and provide hope to patients with glioblastoma. The multimodal approach to treating GBM offers the best chances for extending survival and improving patients' quality of life. Although current therapies do not significantly prolong life expectancy, the combination of new strategies and continuous research promises progress in understanding and combating this deadly tumor.