The invention relates to a method for enriching and separating flavones in cedrela sinensis leaves by an aqueous two-phase system, the cedrela sinensis leaves are firstly dried and crushed, crude extract liquid of the cedrela sinensis leaves is obtained after reflux extraction and impurity removal, ammonium sulfate and ethanol are added according to the proportion after concentration, heating andthe even mixing are carried out, thereby being split into upper and lower phases; the flavones are mainly distributed in the upper phase containing the ethanol and further concentrated and purified. The lower phase is cooled, crystallized and filtered after splitting the upper and the lower phases, ammonium sulfate crystals are recovered; anhydrous ethanol is added in the upper phase liquid for precipitating, removing the ammonium sulfate and other residual impurities and then recovering the ethanol, and a product is obtained by vacuum drying the concentrated liquid. The method has the advantages of rapid phase split, integrated process and improves the concentration and purity of the flavones in the upper phase; the material consumption is reduced, the toxicity is small, the ethanol and the ammonium sulfate are easy to be recovered and utilized; the recovery rate of the flavones in the cedrela sinensis leaves is high, the production method is simple, easy to master and not affected by the environment; the cost is low, and the method is applicable to industrial production.