Abstract: The aim of this experiment was to break the cells of lactic acid bacteria using lysozyme.The best conditions were screened out to get the highest yield rate of protein.A central point was determined by single factor experiment to design a model in accordance with Box- behnken, applying response surface analysis methodlogy to optimize the extraction conditions.The result showed that pH value of 7.73, extraction temperature of 52℃, extraction time of 1.7h and enzyme dosage of 3.0mg /g, an optimum yield rate of protein was obtained.The yield rate of protein was most significantly affected by extraction time, followed by enzyme dosage, pH and extraction temperament.Under the optimum conditions, yield rate of protein was 49.43%.