Microwave technology is applied in sterilization of soybean paste on three main parameters as power,time and net weight.The effects of these parameters are compared by colony forming unit to obtain the optimum microwave sterilization process.Sensory evaluation and color difference of the soybean paste that is microwave sterilized and pasteurized are also tested.The evaluation indicated that three parameters,power,time and net weight all have obvious influence on colony forming unit in the soybean paste.Technical parameters for optimization are microwave power of 3400 W,microwave time of 120 seconds and net weight of 100 gram per package.After the process,colony forming unit of sterilized samples decreases by 99.9%,Coli form bacteria is less than 3.0 MPN/g and has good quality according to the Hygienic standard for soybean paste in China.Change in quality of the soybean paste,especially the color,is even less noticeable after pasteurization.