The medical records of six dogs with primary intranasal transmissible venereal tumour (TVT) were reviewed. Epistaxis (4/6), serosangineous nasal discharge (2/6), oronasal fistulae (2/6), facial swelling (1/6) and submandibular lymphadenopathy (3/6) due to reactive hyperplasia (2/3) and metastasis (1/3) were the most common complaints and clinical findings. Diagnosis was made by rhinoscopy and confirmed by cytology and histopathology in five dogs and by cytology only in one dog. The microscopic appearance of the tumours with both diagnostic techniques was typical of TVT. Four cases were treated effectively with four to five weekly cycles of vincristine monotherapy that resulted in complete resolution of TVT masses in approximately 1 month. One case was resistant to this kind of treatment and another one was lost to follow-up.