A positive selection system was developed for Agrobacterium-mediated trasnsformation of using hypocotyl segments of aseptic seedlings of chinese cabbage as explants, regenerated plants with kanamycin resistance were obtained. The transformed plants with CryIA( c) (Bt) gene were confirmed by Southern blotting analysis, indicating the integration of the transgene into the cabbage genome. Majority of the transgenic plants had only a single copy of the inserted CryIA( c) gene. Leaf section bioassays showed that resistance against larvae of diamondback moth in CryIA( c) transgenic cabbage was significantly enhanced. The inheritance patterns of the transgene in T(1) offspring of transgenic cabbage were investigated using PCR analysis and kanamycin resistance test on young seedling leaves.