Real-time, quantitative characterization of cells at single-cell resolution, particularly while maintain- ing their intrinsic properties and without affecting cellular processes, is of primary importance in modern biological assays. Dielectrophoresis is a label-free, real-time, and quantitative technique, and is amenable to integration with other techniques, thus providing new and powerful tools for biology and medicine. In this study we present dielectrophoresis as a characterization tool for Mycobacterium smegmatis single cells. Understanding how phenotypically variant M. smegmatis cells respond dielectrophoretically when subject to the same electric field, could reveal underlying membrane altering mechanisms related to cell death, drug-tolerance, and drug-resistance. In this study, we dielectrophoretically characterized live, heat-treated and antibiotic-treated bacteria. Our results present quantifications of cellular behaviors associated with membrane-specific cell damages and demonstrate adequacy of dielectrophoretic devices in point-of-care diagnostic and monitoring for bacterial infections.