Abstract: In order to improve the relative extraction rate of polysaccharides from Radix Notoginseng (RNP) , the extraction conditions of inner ebullition of RNP was optimized by single factor experiment and response surface methodology (RSM) .The optimum level of extraction temperature, solid to liquid ratio and extraction time were determined by single factor experiment.Based on this, the second- order polynomial equation for RNP extraction was established by Box-Behnken design and RSM.The optimum extraction conditions were obtained as followed:extraction temperature of 89℃, solid to liquid ratio of 1 ∶ 19, extraction time of 5min.Under the optimal extraction conditions, the relative extraction rate of RNP could reach 84.86%.Inner ebullition method is a safe, effective and simple method to extract effective components of plants.