Abstract: ObjectiveTo compare the protein expression profiles of multi-drug-resistant.Mycobacterium tuberculosis isolate with dmg-sensitive isolate, and to provide basis for further study on molecularm echanisms of drug-resistant tubereulosis.MethodsThe bactrerial proteins were analyzed with two dimensional electrophoresis.Computer software was used to compare the two dinensional electrophoretic maps.Some differentialprotein spots were cut off from the gel and subiected to mass spectrometer(MS) analysis.ResultsTwenty-seven differential protein spots were found bettyeen the multi-drug-resistant isolate and the drug-sensitive isolate Six protein spots were obviously up-regulated in the multi-drug-resistant isolate.MS detection showed the six protein spots were inorganic pyrophosphatase, peptidyl-prolylcis-transisomerase A,elongation factor Tu, unnamed protein, dioxygenase and moxR protein.ConclusionProtein expression differences were discovered between multi-drug-resistant.Mycobacterium tuberculosis isolate and drug-sensitive isolate.Further study on the functions of these differential expression proteins might be helpful in elucidating the molecular mechanisms of drug-resistant tuberculosis.