Radiologic manifestations of pulmonary tuberculosis (TB) can vary according to several host factors, including prior exposure to TB, age, and underlying immune status. Although chest radiography is the mainstay in the evaluation of pulmonary TB, CT generally is required to detect fine lesions overlooked on chest radiographs, to define equivocal lesions, or to evaluate complications. High-resolution CT is useful in understanding the pathologic process of the disease and in determining disease activity in selected cases. This article describes the characteristic CT findings of various forms of pulmonary TB and nontuberculous mycobacterial infection according to immune status of the patients, and assesses the role of CT in the diagnosis and management of pulmonary TB.