DNA polymerase activity which sedimented at about 7s in the presence of 0.5M KC1 increased in cultured kidney cells after infection with a chicken embryo lethal orphan virus, an avian adenovirus. Elevated levels of antigenic material to a monoclonal antibody specific for the large subunit of chicken DNA polymerase alpha were also detected in nuclei of virus-infected cells by an immunofluorescence method. Since the elevations of DNA polymerase activity and of nuclear immunofluorescence was not inhibited with 1-beta-D-arabinofuranosylcytosine, the early viral gene(s) seems to be responsible for the induction of the synthesis and nuclear accumulation of DNA polymerase alpha.