Using organic solvent method to extract polyphenols in lentils, the extraction process was optimized by making response surface experiment. Results of the study indicated that, when the mass ratio of solid and solvent was 190︰1 (V︰m); the temperature was 82.60 ℃; the concentration of acetone was 12.96%, a better extraction effect could be obtained, and the average extraction rate could reach 26.94%(m/m). High performance liquid chromatography (HPLC) analysis has showed that the polyphenols of lentils which extracted by this method were mainly composed of vanillin, p-coumaric acid, rutin and quercetin.