Abstract: The ultrasonic wave-assisted extraction technology and macroporous resin was used to extract and purify oleanolic acid from dried fruit of Chaenomeles sinensis(Thouin) Koehne through quadratic rotation-orthogonal combination design. Macroporous resin was chosen with static adsorption and desorption experiments, and the optimum purification parameters were established with dynamic adsorption and desorption experiments. Results indicate that the optimum extraction conditions are as follows: ultrasonic power is 600W, temperature is 53℃, the ratio of liquid to solid is 8︰1, ultrasonic treating time is 70min, reflux extraction time is 120min, the extraction rate of oleanolic acid is 3.000 mg/g; XDA-1 resin is favorable in purification of OA in Chaenomeles sinensis(Thouin) Koehne, the optimum purification conditions are found to be 0.794 mg/mL of OA concentration, the flow rate of adsorption is 0.5 mL/min; the desorption solvent is 90% ethanol, and the flow rate of elutant is 1.0 mL/min. the content of OA can be increased up to 26.55% after being purified by XDA-1 resin.