Abstract: Canine Influenza Virus (CIV) infection caused severe and acute respiratory symptoms. In recent years, surveys of CIV infection in dogs have been reported worldwide. It has received considerable attention from veterinarians, virologists and epidemiologists. This study shows that CIV infected beagle dogs developed some histopathological changes. These can clarify the prevalence of CIV infection, the CIV mechanism of pathogenesis and provide experimental evidence in beagle dogs.