The supersonic assistance extraction processing of total flavonoids from Cyclocarya paliurus leaves was studied. By means of orthogonally rotational combination design with four factors (ratio of solvent to dry Cyclocarya paliurus leaves，extraction time，ultrasonic power and ethanol concentration) as influence factors, the optimal extraction technology was performed. The results indicated that the effect of factors on the extraction was in the order as follows, extraction time, the most important one, then ethanol concentration, ratio of solvent to dry Cyclocarya paliurus leaves, and ultrasonic power as the last one. The optimum conditions were ratio of solvent to dry Cyclocarya paliurus leaves 55mL/g, extraction time 34min, ultrasonic power 720W, and ethanol concentration 60 percent. With the optimized technology, the content of total flavonoids in the final product is 86.63 percent. In conclusion, the technology is relatively stable and reliable, and consistent with the validate experiment result.