Four different kinds of phenolic acids of Hovenia acerba fruit were prepared by acid or alkaline hydrolysis and organic solvent extraction.And they are soluble free phenolic acids(SFPA),soluble esterified phenolic acids(SEPA),soluble glycoside phenolic acids(SEPA) and methanol-insoluble ester-bound phenolic acids(ISPA).The spectral characteristics were studied by scanning Ultraviolet Spectrum in the range of 200~800 nm.The total phenolic acids content and the antioxidant activity of different kinds of phenolic acids of Hovenia acerba fruit were determined by Folin-Ciocalteu method,and DPPH,ABTS+,and Fe3+ methods,respectively.Results indicated that the crude extraction and four different phenolic acids have different spectral characteristics in ultraviolet band.The total phenolic acids content of ISPA is striking higher than the three kinds of soluble phenolic acids.The order of total phenolic acids content is ISPA > SEPA >SFPA >SGPA.Antioxidant activities of ISPA is also markedly stronger than the three kinds of soluble phenolic acids.