On the basis of single-factor test, the extraction conditions of total phenolics (TP) and total flavonoids (TF) from fruits of Phellodendron amurense were analyzed and optimized by the Box-Behnken design, and studied the antioxidant activity of the extracts to determine their correlation. Results showed that, the optimal extraction conditions are as follows: ethanol volume fraction 43%, extraction temperature 72 ℃, pH value 11, ultrasonic power 500 W, liquid/material ratio 30:1 (mL/g), and extraction time 40 min. The yield of TP (expressed as mg of Gallic acid (GA) per gram P. amurense fruit) and TF (expressed as mg of rutin (RT) per gram P. amurense fruit) were 7.09 ± 0.38 mg GA/g and 20.41 ± 0.47 mg RT/g under these conditions. Results showed that there is a significant correlation between in vitro antioxidant activity and contents of TP and TF（P＜0.01）.and TF（P＜0.01）. This work would provide a basis for the further development of P. amurense.