The segregation, integration and stability of the transgene-Bt (Bacillus thuringensis) in eight transformants created by three ways of transformation were studied by means of PCR (Polymerase chain reaction) and DNA molecular hybridization. The results are as follows: (1) The transgene-Bt in most of the progenies of the transformants showed simple Mendelian segregation. Although some deviation from Mendelian fashion existed in the early generations, the normal Mendelian segregation would be found after R3 generations and the transgene could fix in the populations. (2) The integration patterns of the transgene varied to the some extent in the different transformants, but they were characterized by either smaller band and copy numbers or cascade integration or closely linked integration in all transformants. (3) Changes of the Southern land pattern were found in some families of some transformants, especially, in the two families of Ding 4R5.