Studies were made on extracting polyphenol from pre-germinated brown rice.The effects of ultrasonic extraction time,ethanol concentration and proportion of material and solution on yield were discussed.Box-Behnken center-united experiment design and response surface methodology were used to optimize the extraction technology of polyphenol of pre-germinated brown rice.The optimal conditions of extraction were concluded as follows: ultrasonic extraction time 11.08min,ethanol concentration 80%,proportion of material and solution 1∶ 17.62.the actual detection value of polyphenol extraction rate was 60.13 μg/g,that is almost equal to the predictable value.