Abstract: Objectives To summarize the clinical features and relevant factors of 203 cases with infantile pulmonary tuberculosis. Methods Clinical data of 203 infantile with pulmonary tuberculosis were retrospectively reviewed. Results Among 203 infants, 127 (62.6%) were from country, 76 (37.4%) from city; 64.5% of city infants have received BCG vaccination, which is higher than 46.5% in country infants ; 78 cases (38.4%) have clear evidence for active tuberculosis exposure, 26 cases (12.8%) have suspicious tuberculosis exposure; 175 cases (86.2%) have fever, 165 cases (81.3%) have respiratory symptoms, 107 cases (52.7%) have pulmonary signs, 80 cases (39.4%) have hepatosplenomegaly; Etiology was confirmed in 91 cases (44.8%); 54.7% of patients were found with concurrent extrapulmonary tuberculosis, and the most commonly seen was formis tuberculous meningitis. In this study, the misdiagnosis rate is 39.9%, and 84.0% patients were often misdiagnosed as bronchial pneumonia; Vaccinated BCG rate is lower in infants with severe tuberculosis (44.83%) than that of infants with mild tuberculosis (74.14%). Conclusions Infantile pulmonary tuberculosis is featured with acute onset, severe clinical performance and easily complicated with extrapulmonary tuberculosis, atypical clinical performance, and high misdiagnosed rate which needs early detection and diagnosis. Unvaccinated BCG and active tuberculosis exposure were important clues for the diagnosis of infantile pulmonary tuberculosis.