The clinical importance of the thyroid nodules in patients with axial spondyloarthritis (ax-SpA) rests with the need to exclude thyroid malignancy. The aim of this study is to assess the risk of thyroid malignancy in ax-SpA patients receiving anti-TNF therapy. From September 2015 until December 2015, 70 patients diagnosed with ax-SpA were included in the research. Forty of the patients had received anti-TNF therapy, and 30 of the patients were anti-TNF naive. All cases were screened for the presence of nodules in the thyroid gland with ultrasound. Of the patients that received anti-TNF therapy, 15 (37.5%); and of the anti-TNF naive patients, 11 (36.7%) had thyroid nodule(s). Four patients from the anti-TNF group underwent fine needle aspiration biopsy of the nodules, and two of them were diagnosed with papillary thyroid carcinoma. None of the nodules in anti-TNF naive patients required biopsy. When compared to the normal population, the standardized incidence ratio (SIR) was found to be increased in both male (SIR 2.03, 95% CI 1.9 to 18) and female (SIR 2.7, 95% CI 2.6 to 24) cases. It is not yet established whether the development of cancer during the treatment process is the effect of the treatment or if it is a part of the natural course of the disease or if it is coincidental. We saw a mild increase in thyroid malignancies in ax-SpA patients who received anti-TNF therapy. Therefore, we believe that the thyroid gland should also be taken into consideration while screening for malignancy before anti-TNF therapy.