Objective To observe effect of Levofloxacin gel against Mycobacterium tuberculosis in vitro and safty of bronchial intervention therapy. Methods The MIC and MBC of Levofloxaein and Levofloxacin gel were measured by handwork and instrument methods, the safety of Levofloxacin gel was assessed by bronchial intervention therapy using rabbits as experiment animals. Results The MIC of Levofloxacin gel to M.tubereulo H37Rv, M.boris and M.phlei was 0.5,0.5 and 1.0 mg/L; the MBC of that was 1.0 ,1 .0 and 1.5 mg/L respectively. The MIC and MBC of Levofloxacin gel and Levofloxacin had no significant difference without any harmful effect. Conclusion the effect of Levofloxacin gel and Levofloxacin against Mycobacterium tuberculosis was equivalent, carbomer in the formulation did not affect the activity of Levofloxacin against Mycobacterium tuberculosis; meanwhile Levofloxacin gel which contains carbomer was safe in bronchial intervention therapy.