[Objective] The aim was to screen method for extracting polysaccharide from Sonchus oleraceus L. [Method] Ultrasonic wave, microwave irradiation and Ultrasonic-microwave synergistic extraction method were designed to compare with water bath method. With extraction rate of crude polysaccharide as an indicator, the methods were evaluated. [Result] Four extraction methods all have significant effects on extraction rate of S. oleraceus polysaccharide(P<0.05), the extraction rate of ultrasonic-microwave synergistic method was highest as 23.16 %,followed by microwave, water bath and ultrasonic wave, with extraction rate as 22.33 %, 20.98 % and 19.54 %. [Conclusion] Ultrasonic-microwave synergistic extraction method was best, accurately weigh 5.0 g S. oleraceus dry powder, add 100 ml distilled water, after mixing, put on ultrasound-microwave instrument to extract. Ultrasonic power was 50 w, frequency was 50 kHz; microwave frequency was 2 450 MHz. Under 80 ℃,extracting for 30 min, and through filtering, residue repeat extraction for 1 time, collecting filtrate, with 200 ml as constant volume, the polysaccharide content was determined. With glucose as standards, choosing anthrone-sulphuric acid colorimetry, the linear range of glucose concentration was 10-100 mg/ml, colorimetric wavelength was 620 nm, the average recovery rate was 100.29%, RSD value was 0.22% (n=5). [Objective] The aim was to screen method for extracting polysaccharide from Sonchus oleraceus L. [Method] Ultrasonic wave, microwave irradiation and Ultrasonic-microwave synergistic extraction method were designed to compare with water bath method. With extraction rate of crude polysaccharide as an indicator , the methods were evaluated. [Result] Four extraction methods all have significant effects on extraction rate of S. oleraceus polysaccharide (P <0.05), the extraction rate of ultrasonic-microwave synergistic method was highest as 23.16% followed by microwave, water bath and ultrasonic wave, with extraction rate as 22.33%, 20.98% and 19.54%. [Conclusion] Ultrasonic-microwave synergistic extraction method was best, accurately weigh 5.0 g S. oleraceus dry powder, add 100 ml distilled water, after mixing, put on ultrasound-microwave instrument to extract. Ultrasonic power was 50 w, frequency was 50 kHz; microwave frequency was 2 450 MHz. Under 80 ° C, extracting for 30 min, and throug With glucose as standards, choosing anthrone-sulphuric acid colorimetry, the linear range of glucose concentration was 10-100 mg / ml, colorimetric wavelength was 620 nm, the average recovery rate was 100.29%, RSD value was 0.22% (n = 5).