Aim. Many studies demonstrated that alopecia areata (AA) and vitiligo are commonly associated with autoimmune thyroid diseases. We aimed to investigate the frequency of thyroid dysfunctions and autoimmunity related with vitiligo and AA. Material and Methods. 200 patients, 92 AA and 108 vitiligo diagnosed, were surveyed retrospectively. The control population was in reference range and from Konya, central Anatolian region of Turkey. Thyroid function tests (free T<inf>3</inf>, free T<inf>4</inf>, and TSH) and serum thyroid autoantibody (anti-TG, anti-TPO) levels were evaluated in all patients. Results. In vitiligo patients, 9 (8.3%) had elevated anti-TG levels and 16 (14.8%) had elevated anti-TPO, and in 17 patients (15.7%) TSH levels were elevated and 3 (2.8%) patients had elevated fT<inf>4</inf> levels and 5 (4.6%) had elevated fT<inf>3</inf> levels. Within AA patients, 2 (2.2%) had anti-TG elevation and 13 (14.1%) had anti-TPO elevation, in 7 patients (7.6%) TSH were elevated, and in 1 patient (1.1%) fT<inf>4</inf> were elevated and 5 (5.4%) patients had elevated fT<inf>3</inf> levels. Conclusion. In our study, impaired thyroid functions and thyroid autoantibodies in vitiligo and AA patients were identified at lower rates than the previous studies. According to results of this study there is no need for detailed examination in alopecia areata and vitiligo patients without clinical history.