In this study, some important parameters were optimized for effective extraction and purification of total flavonoids from corn silk, and the anti-hyperlipidemic activities was analyzed in rabbits by feeding experiment. Firstly, the high extraction yield (5.32 mg·g-1) of total flavonoids were obtained under the optimal extraction conditions, which are 80°C for 3 h with corn silk over 60% ethanol ratio of 1:30. Then, the AB-8 resin was selected for the purification of flavonoids due to the higher static adsorption and adsorption capacity than other resins. The optimum conditions for purifying flavonoids as follows: for adsorption, sample concentration was 2.542 mg·mL-1, pH was 3.7, processing volume was 4 BV; flow rate was 2 BV·h-1; temperature was 25°C. For desorption, elution solvent ethanol-water (95%, v/v) solution was 4.5 BV; flow rate was 2.0 BV·h-1. Flavonoids with content of 68.3% were obtained with a flavonoid recovery of 93.7%. The results showed that AB-8 resin revealed a good ability to purify total flavonoids. Lastly, feeding experiments results indicated that flavonoids had significant anti-hyperlipidemic activities to rabbits by reducing the content of serum total cholesterol (TC), triglycerides (TG), and low-density lipoprotein-cholesterol (LDL-C) and increasing the concentration of high-density lipoprotein-cholesterol (HDL-C).