Flavonoids was extracted from the bark of Tilia amurensis using ethanol as extraction solvent by oscillating method. The influences of ethanol concentration，extracting time，extracting temperature and ratio of material to liquid on extracting yield were studied. The results of response surface analysis showed that the order of influencing factor was ethanol concentration, the ratio of material to liquid, extracting temperature and extracting time. The optimum extracting conditions were as followed: ethanol concentration 68%, extracting time 153min, extracting temperature 60℃ and the ratio of material to liquid 1∶40 (g∶ml). Under these conditions, the extraction yield of flavonoids was 5.522%.