A six-month-old intact male rottweiler presented with papillomatous growths protruding from the oral mucous membranes. A tentative diagnosis of canine oral papillomavirus (COPV) infection was made based on the gross appearance of the numerous lesions and the young age of the patient. Two warts from the oral mucosa were removed surgically for further diagnostic investigations. The viral aetiology of the diseases was confirmed by histopathological and electron microscopic findings, and by the identification of specific COPV DNA is removed oral papillomatous tissue. The patient was followed clinically and complete regression of the oral lesions occurred after four weeks. Neither the route of transmission nor the source of infection was found. Immunodeficiency as a contributing aetiological factor to the development of COPV-induced lesions as discussed.