Background: Anti-TPO antibodies are one of the characteristic factors in autoimmune thyroiditis (AIT). Previous studies reported a high prevalence of anti-TPO antibodies (Abs) in Iran. We have therefore assessed the prevalence of anti-TPO Abs in Gorgan, Iran. Methods: This cross-sectional study, conducted from 2015 to 2018 in Gorgan city, Northeast of Iran. The Participants included women with Poly cystic ovary syndrome (PCOs), celiac patients, men with hepatitis C infection, and age and sex-matched controls. ELISA method was used for the analysis of laboratory tests. Results: The number of enrolled subjects in PCOs, celiac disease, and Hepatitis C infection groups were 76, 67, and 60, respectively. Anti-TPO Abs positivity was significantly higher in patients with PCOS than in the control group (18. 4% vs. 0. 00%,p = 0. 000). There were no significant differences in the frequency of anti-TPO Abs positive cases between CD patients and the controls (26. 9% vs. 21. 1% p =0. 413). The incidence of anti-TPO Abs positivity was significantly higher in the control group (10% vs. 25%,P = 0. 031). Conclusion: Very high level of anti-TPO Abs was observed in both patients and healthy population in Golestan province. Considering this rate and its association with autoimmune disorders, it is suggested to prioritize screening programs for related disease in this area.