In order to reveal the biological mechanism of transformation induced by ultrasound and convenient to the industrial application of Bacillus subtilis,this study utilize the mechanism that ultrasound can produce a series of non-thermal effect through aeroacoustic and cavitation,which lead to short cells membrane permeabilization generation,to induce plasmid pET28a transform for Bacillus subtilis.The results showed : a certain condition can successfully induce plasmid pET28a transform for Bacillus subtilis;because of losing water and the release of intracellular substances,the cells treated by ultrasound are irregularity and plicated under the electron microscope;the test of proteins,phospholipids and AP suggested that because ultrasound change the structure of cell wall and permeability of cell membrane,a large of intracellular substances release to extracellular.Maybe those can provide some thinking and base on revealing the biological mechanism of transformation.