The paper was to study DPPH(1,1-diphenyl-2-trinitrobenzene hydrazine) scavenging ability of different concentrations of flavonoid and polysaccharide from dandelion. Flavonoids were extracted from dandelion using alcohol precipitation ultrasonic extraction method and polysaccharide was extracted using water ultrasonic extraction method. DPPH free radical scavenging ability of flavonoid and polysaccharide was determined using ultraviolet spectrophotometer method.The difference in DPPH free radical scavenging ability between flavonoids and polysaccharide was analyzed statistically. The results showed that DPPH scavenging ability was the best when the concentration of flavonoid was 1. 6 mg/m L; the scavenge rate was up to 96. 11% and IC50(median inhibitory concentration of inhibitors) was 0. 38 mg/m L. DPPH scavenging ability was the best when the concentration of polysaccharide was 1. 4 mg/m L; the scavenge rate was 89. 33%and IC50 was 0. 51 mg/m L. Statistical results showed that there were significant differences in DPPH free radical scavenging ability between dandelion flavonoid and polysaccharide( P < 0. 05). Flavonoid had significantly higher scavenging ability than polysaccharide( P < 0. 05). The study lays a theoretical foundation for further research on dandelion flavonoid,and provides a theoretical basis for development and utilization of dandelion resources. The paper was to study DPPH (1,1-diphenyl-2-trinitrobenzene hydrazine) scavenging ability of different concentrations of flavonoid and polysaccharide from dandelion. Flavonoids were extracted from dandelion using alcohol precipitation ultrasonic extraction method and polysaccharide was extracted using water ultrasonic extraction method DPPH free radical scavenging ability of flavonoid and polysaccharide was determined using ultraviolet spectrophotometer method. The difference in DPPH free radical scavenging ability between flavonoids and polysaccharide was analyzed statistically. The results showed that DPPH scavenging ability was the best when the concentration of flavonoid was 1 6 mg / m L; the scavenge rate was up to 96. 11% and IC50 (median inhibitory concentration of inhibitors) was 0. 38 mg / m L. DPPH scavenging ability was the best when the concentration of polysaccharide was 1. 4 mg / m L; the scavenge rate was 89. 33% and IC50 was 0. 51 mg / m L. Statistical results showed that there w ere significant differences in DPPH free radical scavenging ability between dandelion flavonoid and polysaccharide (P <0.05). Flavonoid had significantly higher scavenging ability than polysaccharide (P <0.05). The study lays a theoretical foundation for further research on dandelion flavonoid , and provides a theoretical basis for development and utilization of dandelion resources.