Cancer is still the leading cause of death in developed countries. Oncolytic virus (OV) therapy is a promising new strategy for tumor growth inhibition. Despite the fact that the oncolytic function of some viruses was discovered in the last century, it has not been properly applied and recognized. The viruses of the Paramyxoviridae family, particularly Newcastle disease virus (NDV), are powerful oncolytic and immunostimulating agents non-pathogenic in humans. NDV is characterized by a selective infection and spread of the virus in tumor cells, direct cytopathic effect, and indirect induction of the innate and adaptive immune system of the host. However, intratumoral administration of OVs is not always possible and results in only local effect. There is an assumption that immune system cells can be used as possible carriers of OVs to provide temporary protection against immune system factors of the body. Dendritic cells (DCs) were the most effective cellular carriers among numerous types of immune cells evaluated in studies of the OV effect. In conclusion, the authors suggest that the use of OVs as an adjuvant for tumor antigens in the development and improvement of DC vaccine optimizes the development of antitumor immune response, STAT - signal transducer and activator of transcription.