Abstract: ObjectiveTo explore the risk factors of pulmonary tuberculosis(PTB)in the southern army of China and to lay foundation for their prevention and control.MethodsA case-control study on the risk factors of PTB was carried out in the southern army of China,138 case and 276 controls were selected.ResultsSingle factor conditional logistic regression analysis showed that the occurrence of PTB was closely associated with body indices,family income,family history of PTB, area of enrollment,history of exposure to PTB,go home to visit one's family,contact with people,intension of work before sicken one month,and history of Bacille Calmette Guerin(BCG)vaccination was protective factor.Further multivariable logistic regression analysis turned out that body indices,famlly history of PTB(r=1.79),history of exposure to PTB(r=2.96),go home to visit one's family(r=2.83),contact with people(r=2.24),intension of work(r=1.68)before sicken one month were the independent risk factors of PTB,history of Bacille Calmette Guerin(BCG)vaccination was inversely associated with PTB in army.ConclusionThe main risk factors of PTB were contact with people,area of enrollment,history of exposure to PTB obviously in the southern army of China.History of BCG vaccination was a protective factor of PTB.