Abstract: In order to optimization of extraction process of polyphenol oxidase from seedless white Grape,this study extracted polyphenol oxidase from seedless grape with acetone extraction,ultrasonic assisted extraction and buffer solution extraction. On the basis of the liquid ratio,extraction time and buffer pH,the extraction conditions of the polyphenol oxidase were optimized by using the response surface method. The results showed that the optimum extraction conditions of polyphenol oxidase as follows:the liquid ratio was 1:1.8 (g/mL),the extraction time was 2.9 h,the buffer pH was 5.8,the specific activity of polyphenol oxidase was(378.12±1.3) U/mg,which was similar to the predicted value. Response surface analysis could predict the test results more accurately in order to provide the basis for the purification,characterization and structure study of the polyphenol oxidase for the seedless white grapes.