Background: There are many reports on the association between anthracosis and tuberculosis. This study focuses on bronchial anthracosis and associated diseases in the province of South Khorasan-Iran.Methods: This case-series study is performed on patients referred to the Vali-e-Asre Hospital (South Khorasan-Iran) for bronchoscopic evaluations during the period of 2009-2012. Written informed consents were obtained prior to bronchoscopic evaluations. The criterion for diagnosis of bronchial anthracosis was black pigmentation on direct observation of bronchus. Bronchial anthracosis was classified into simple (without deformity) or complicated (with deformity). Pulmonary tuberculosis (TB) was diagnosed either by acid fast staining and culture of liquid samples, or histopathology examination of biopsy. Spirometry was performed to determine the obstructive or restrictive pattern. Results: Among 279 patients who underwent bronchoscopic evaluations, 89 patients, including 34 males (38.2%) and 55 (61.79%) females, were diagnosed with anthracosis. Simple and complicated anthracosis were observed in 42 (48.2%) and 47 (52.8%) cases respectively. Mean age of patients was 72.23±9.65 years. There were 43 (48.3%) cases of tuberculosis (28 cases with complicated and 15 cases with simple anthracosis) (P=0.021). Chest X-ray showed consolidation/infiltration, reticular/fibrotic, and mass/nodule/hilar prominence in 57 (64%), 26 (29.21%) and 6 (6.74%) cases, respectively. Bronchitis was reported in 42 (%59.15) out of 79 patients whose biopsy samples were taken. Spirometric patterns were obstructive, restrictive, upper airway obstruction, and normal in 45 (50.56%), 32 (35.95%), 2 (2.24%), and 10 (11.23%) patients respectively. Conclusion: Tuberculosis is the most frequent disease associated with anthracosis in South Khorasan province. Consequently, patients with anthracosis must be carefully evaluated for tuberculosis.