Our previous studies revealed that the ethanol extract from P.aquilinum exhibited remarkable anti-oxidative activity in vitro.In this paper,the potential antioxidants components of diffident parts of P.aquilinum were investigated by bioassay-guided method.Ethanol extracts from dry P.aquilinum powder were further purified by petroleum ether,chloroform,ethyl acetate,n-butanol to obtain the crude flavonoids.Then the flavonoid contents and the antioxidant activity of the five extracting together with the total ethanol extracts were compared by colorimeter and superoxide scavenging ability by chemiluminescence,respectively.The results showed that remarkable varieties in both total flavonoid contents and antioxidant capacity were existed in six extractions.The potential antioxidant components were mainly in ethyl acetate,in which the flavonoids were obviously much more abundant than the other parts.This might provide us a new strategy for searching new antioxidant from this flavonoid-rich plant and revealing the possible pharmacodynamic material from P.aquilinum.