The present work was undertaken to apply mitotic index as an indicator in the prognosis of cutaneous tumours in dogs. Out of the 103 samples collected from the Madras Veterinary College, Teaching Hospital, Chennai, mitotic index was analyzed by light microscopy on formalin fixed paraffin embedded section of selected 53 canine cutaneous tumours. Mitosis was noticed in all the type of tumours. But the mitotic figures were more in all the malignant tumours when compared to the benign tumours. Among the malignant tumours, metastasis and death rate was higher.