An association between vitiligo and autoimmune thyroid disorders had previously been postulated. Thyroid disorders were found in 18.5% of 15,126 patients with vitiligo, on the basis of the anamnestic data. Then, we investigated 255 healthy relatives in whom we tested only T3, T4 and TSH. With the immunological investigation we detected a higher incidence of TMA in vitiligo patients and in the family members. Therefore, on the basis of the immunologic and thyroid pathology functional data, we observed a thyroid pathology in 25% of the 890 vitiligo patients and in 21.1% of their first degree relatives. Then, clinical observation enabled to discover that 3 of 15,126 patients had undergone exeresis for a thyroid carcinoma and in the 890 vitiligo patients, who had undergone particular investigations, we found a thyroid carcinoma in 3 subjects. In one case lymphnodal involvement and bone metastases in the maxillary district were found. The purpose of this work is to evaluate the incidence of thyrosis and of thyroid carcinoma in vitiligo patients observed for 20 years.