The extraction of phenolic compounds from walnut leaves.The antioxidant activity of phenolic compounds from walnut leaves was investigated by measuring its scavenging ability on hydroxyl radicals and superoxide radicals and the effect of phenolic compounds from walnut leaves to walnut oil was evaluated.The results indicated that phenolic compounds from walnut leaves had good antioxidant activity.The scavenging activity of phenolic compounds for hydroxyl radicals and superoxide radicals were 535 and 68% when the concentration was 1 mg/mL.And when the additive quantity of the extract reached 0.05%,the antioxidant of walnut oil was stronger than that of walnut oil.To study on antioxidant activity of phenolic compounds from walnut leaves,we can make full use of rsources of walnut leaves.