Abstract:Ethanol or methanol was often employed to extract olive leaves.Water was adopted as the extraction solvent and the difference in active components and antioxidant strength was evaluated.Olive leaves were extracted by ultrasound treatment with water，44 % ethanol，and 80 % methanol，respectively.The content of total polyphenols，total flavonoids，hydroxytyrosol，and oleuropein in the extracts were determined.The scavenging rates of the extracts against DPPH·，ABTS+·，hydroxyl free radicals，as well as the reducing power，were compared.Principle component analysis was conducted with SPSS19.0 software to assess the correlation relationship between the active components and antioxidant activity.By dimensionality reduction analysis，the principle components representing the extracts were obtained and the total scores of principle components were calculated based on the characteristic values and contributory rates to variance.The total score of water extract，ethanol extract，and methanol extract was 249.87，-136.89 and-112.98，respectively.The results implied that the water extract from olive leaves was superior in active ingredients and antioxidant activity over ethanol and methanol extracts.It had great potential to be developed into market products.