Up to the present, various viral vectors aimed at gene transfer or therapy have been developed and applied in biological and medical research fields. Pseudotype or recombinant VSV are useful tools as alternative viruses to study entry mechanisms, identification of novel cellular receptors, screening antiviral libraries, or development of serological diagnosis for various kinds of viruses, especially unmanageable BSL-3 or -4 viruses. These viruses have also been applied in targeting vectors to specific cells. VSV vectors with monoclonal antibodies against specific oncogenic proteins or viral receptor molecule(s) incorporated on virion surface have been targeted specifically to cells expressing oncogenic proteins or infected cells expressing the viral envelope proteins, respectively, without any influences on normal or uninfected cells. This raises the possibility of the elimination of cancer cells or chronic viral infections by using acute VSV infection. Genetically engineered VSVs encoding suicide cassettes or immune response genes have also been generated as more specific, safer, and effective agents for cancer therapies. Further studies and applications of VSV vectors will provide us not only with useful tools for virological studies but also various benefits for biological sciences and medical research.