Ilex Cornuta L is an important medicinal plant. Flavonoid compounds are its main biological compontents. AlCl3 method was identified as the appropriate determination method for total flavonoids content of extract obtained from the leaves of Ilex Cornuta L.. The proposed method was validated by the linearity, reproducibility, and recovery experiments. Good linearity was observed with the regression coefficient(R2= 0.999). The recovery rate was in the range of 94.9% and 110.0%, and the relative standard deviation was 2.8%, which indicated that the proposed method was credible. In addition, the extraction parameters including Ethanol concentration, solid-liquid ratio, extraction time and extraction times were optimized by means of an orthogonal design.