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The compositions and antioxidant activities of free and hydrolyzed phenolic acids, which are aglycones of esterified phenolic acids, in wild ginseng leaves were investigated. The contents of free and hydrolyzed phenolic acids in the wild ginseng leaves were 422.4 ± 3.5 and 319.6 ± 5.7 mg/100 g, respectively, as gallic acid equivalents. Free phenolic acids were composed of 55.3% benzoic acid derivatives and 44.6% phenylpropanoids. The major constituents of free phenolic acids in the ginseng leaves were syringic (139.4 mg/100 g) and sinapic (131.2 mg/100 g) acids. On the other hand, hydrolyzed phenolic acids in the ginseng leaves were mainly composed of caffeic (59.4 mg/100 g), ferulic (49.5 mg/100 g), and p-coumaric (33.8 mg/100 g) acids. Phenylpropanoid content was higher (82.7%) than benzoic acid derivatives (17.3%). IC50values of DPPH radical scavenging activity were 10.2?μg/mL for free phenolic acids and 8.0 mg/mL for hydrolyzed phenolic acids, as gallic acid equivalents. Hydrolyzed phenolic acids also exhibited higher hydroxyl and superoxide radical scavenging activities than free phenolic acids did. These results indicated that the antioxidant activities of the wild ginseng leaves were correlated more closely with phenylpropanoid contents than with total amount of phenolics.