Abstract: In this study,response surface analysis was applied to optimize the extraction process of chlorogenic acid from Eriobotrya japonica. On the basis of single-factor experiments,the Box-Behnken center composite experimental design principle was used to design the experiments and the response surface analysis with 4 factors and 3 levels was adopted.A second order quadratic equation for extraction of chlorogenic acid was created.After analyzed the significance of various factors and their interactions,the optimal extraction conditions for the extraction ofchlorogenic acid from E.japonica leaves were determined as follows:70% aqueous ethanol as the extraction solvent,1:15 as sample-to-solvent ratio,50 ℃ as extraction temperature,ultrasonicationfor 30 minand 5 minmicrowavewith 400w as microwave power.The extraction yield of chlorogenic acidwas determined to be 5.84% under the optimized extraction conditions.

Key words: response surface methodology, Eriobotrya japonica leaves, ultrasonic, microwave, chlorogenic acid