Tuberculosis (TB) remains a common disease in the World. Its incidence has risen steadily since 1985, despite a preexisting continuous decreasing of its frequency due to an effective chemotherapy. Nonwhite people, socioeconomically disadvantaged, chronically debilitated groups and AIDS patients are the most concerned. Chest radiography remains the first imaging modality to evaluate TB. Widely radiographic appearances can be encountered, including normal chest X-ray. CT can be useful in all stages of the disease, particularly when clinical and radiological findings are in disagreement and/or when imaging findings are equivocal. CT should be proposed at the end of an effective antituberculous treatment to better subsequently detect fine lesions suggestive of reactivation TB.