en تخصصي Special پژوهشي Research <strong>Objective:</strong> The study evaluated the prevalence and progression of different thyroid tumors in patients who referred to Shahid Sadoughi Hospital during 2005 to 2013, Yazd, Iran.<br> <strong>Materials and Methods:</strong> In this retrospective follow-up study, cytopathological data of patients suffering from thyroid masses was collected during 2005-2013. Age and sex of patients were recorded.<br> <strong>Results:</strong> Totally, 2055 patients were evaluated in this study. The patients were between 21-50 years old .Among the patients, pathological types identified were as follow: 86.8% goiter, 5.8% inflammatory lesions, 3.2% follicular lesions, 3.5%papillary carcinoma and 0.8% follicular neoplasm. Among 2055 patients, 91.7% were women and 8% were men. The frequency of thyroid nodules was increased from 2003 to 2013 with steep slope.<br> <strong>Conclusion:</strong> In total, regarding the current study, different kinds of thyroid tumors had growing trends in recent years and new plan and strategies are recommended to deal with this problem. Thyroid tumors, Follicular neoplasm, Papillary thyroid carcinoma, Goiter, Inflammatory lesions 55 61 http://ijdo.ssu.ac.ir/browse.php?a_code=A-10-30-169&slc_lang=en&sid=1 Mahsa Elahi No Medical Student, Shahid Sadoughi Univercity of Medical Sciencees, Yazd, Iran. Maryam Elahi No Medical Student, Shahid Sadoughi Univercity of Medical Sciencees, Yazd, Iran. Reza Nafisi Moghaddam No Assistant Professor of Radiology, Department of Radiology, Shahid Sadoughi Univercity of Medical Sciencees, Yazd, Iran Masoud Rahmanian Yes Assistant Professor of Endocrinology, Diabetes Research Center, Shahid Sadoughi Univercity of Medical Sciencees, Yazd, Iran