Laboratory-reared female black flies (Simulium vittatum Zetterstedt) were infected experimentally with a 1997 vesicular stomatitis virus New Jersey serotype isolate and allowed to feed on susceptible laboratory mice. All mice exposed to black fly bite seroconverted by day 21 after infection, an indication of virus transmission. In addition, viral RNA was detected in the spleen of several mice. These findings are consistent with the hypothesis that black flies are involved in VSV-NJ transmission during epizootics in the western USA and represent the 1st confirmed example of biological transmission of an arbovirus by a member of the Simuliidae using an animal model.