This study was carried out to identify rapidly ${delta}-endotoxin$ from Bacillus thuringiensis (Bt) subsp. kurstaki HD-1 with proteomic analysis. Protoxin was isolated from sporulated cells and purified by ultracentrifugation using 40-70% sucrose density gradient. Protoxin was treated with trypsin to analyze digested peptides by liquid chromatography-tandem mass spectrometry. The proteomic analysis for detected peptides revealed that this methodology is available for discriminating similar Bt strains by identifying Bt subsp. kurstaki HD-1-specific peptides, suggesting that proteomic analysis can be used for rapid identification of Bt strains.