Dog is the most intimate companion animal of human, and the close contact between humans and dogs raises the possibility that dogs can transmit virus to humans as intermediate hosts. Canine influenza virus (CIV) belongs to Influenza virus A of Orthomyxoviridae family and is a highly emerging respiratory pathogen that can be adapted to new hosts by crossing interspecies barriers. In recent years, cases of dogs infected with various subtypes of influenza virus are reported continuously, including H3N2, H3N8, H5N1, H1N1, H3N1 and H9N2 viruses. Reports indicated that the influenza virus might further acquire the ability to infect dogs. The CIVs not only severely jeopardize the survival and health of dogs, but also bring tremendous risks to human health. During influenza pandemics secondary bacterial infection is the main cause of the mortality. There is dire need to know mechanisms involved in the interaction between Influenza and bacterial species to understand treatment procedures that fight viral and secondary bacterial infection.