---

Background and Objective: Due to the increase of incidence of extrapulmonary tuberculosis in Iran, This study was conducted to determine the epidemiological pattern of extrapulmonary tuberculosis in the Mazandaran province, northern Iran. Methods: This descriptive-analytic study was carried out on medical record of 3313 tuberculosis patients in Mazandaran province, northern Iran during 2001-11. Age, gender, affected year, area and affected organ were gathered for each patient. Results: 843 (25.4%) of subjects were diagnosed with extrapulmonary tuberculosis. The incidence of extrapulmonary tuberculosis increased by 4% for every unit increase in incidence year (P<0.05). The mean age of patients with extrapulmonary tuberculosis was significantly less than patients with pulmonary tuberculosis (42.8±20.6 years vs. 48.7±21.2, P<0.05). Extrapulmonary tuberculosis was significantly higher in women (P<0.05). The chance of extrapulmonary tuberculosis in women was 1.7 times of men. Lymph node (33%) was the most common affected organ followed by pleura (18.9%) and bone (17.7%). Conclusion: The trend of incidence of extrapulmonary tuberculosis was ascending during 2001 to 2011. The most affected organ in extra pulmonary tuberculosis was lymph nodes.