In the paper the current state-of-the-art of the preclinical and clinical trials concerning GM- CSF-secreting tumor cell vaccines was presented. Cytokine gene-modified cancer vaccines are experimental immunotherapeutics applied as adjuvants or as main medications in the treatment of metastatic neoplasms. The principle of their action consists in the delivery of cancer antigens in association with GM-CSF to the patient's organism. The cytokine improves recruitment and activation of dendritic cells, leading to more efficient antigens' presentation. Retroviruses and adenoviruses are the most widely applied vectors for cytokine gene transfer because of the high efficiency. Effectiveness of the vaccine therapy in the preclinical studies, usually in the models of murine melanoma, was high in the prophylactic as well as in the therapeutic model. Phase I clinical trials, carried out in the patients with metastatic melanoma, lung cancer and prostate cancer, confirmed safety of the therapy, indicated augmented immune response in most of the patients, but only some of them experienced prolonged survival in comparison to the prognosis. Phase II and III studies did not reveal the superiority of vaccination over standard therapy so far. The research carried on at the moment are aimed at finding the reasons for limited clinical efficiency of GM-CSF-secreting tumor cell vaccines. Methods of augmenting its effectiveness contain the following main targets: suppressor CD4+CD25+Foxp3+ T-cells, MFG-E8 protein and co-stimulatory molecule CTLA-4.