Abstract: Objective：To summarize multislice spiral thoracic CT findings of pulmonary tuberculosis in infants under 1 year old. Methods：The clinical data and the chest CT results of 38 consecutive infants diagnosed with pulmonary tuberculosis were retrospectively collected and analyzed. Results：There were 10 cases (26.3%, 10/38) of miltaris tuberculosis. Of the rest 28 cases, 22 cases (78.6%) had left lower lobe involvement, 23 cases (82.1%) had right lower lobe involvement, 24 cases (85.7%) had 3 and more pulmonary segments involvement. Mediastinal and/or hilar lymphadenopathies were observed in 31 cases (81.6%). There were 24 cases (85.7%) with lobar and/or segmental consolidation, 18 cases (64.3% ) with bronchial stenosis or occlusion, 19 cases (67.9%) with nodular lesions, 15 cases with ground glass opacity (53.6%), 15 cases (53.6%) with strip lesions, 13 cases (46.4%) with patchy infiltration, 22 cases (78.6%) with 3 or more forementioned lesions. Eleven cases (28.9%) of pulmonary tuberculosis showed calcification. The minimum age is 3 months and 2 days. The calcification foci were completely absorbed after treatment in 3 cases. Conclusions：Pulmonary tuberculosis is more common located in lower lobes with varying forms and multiple lesions in pulmonary lobes and segments in infants. The most common CT features are lymphadenopathy and pulmonary consolidation. Nodular lesions, ground glass opacity, strip lesions, and patchy infiltration are crucial for diagnosis, pulmonary tuberculosis is often associated with bronchial stenosis or occlusion. Calcification foci could be observed early in 3monthold infant and could be completely absorbed after management in some cases.