Abstract: Objective: To study the effect of different extraction agents of Jerusalem artichoke( Helianthus tuberosus)disk in secondary metabolism substance content and in vitro antioxidant activity.Methods: Using the disk powder of Jerusalem artichoke as raw material,the different volume fraction of ethanol,methanol,acetone and other organic solvents were used to extract the samples,the total phenolic and flavonoids content was determined,and three different types of radical scavenging capacities including the FRAP,DPPH and ABTS were chosen to determine the in vitro antioxidant activity of the samples.By ultra performance liquid chromatography( UPLC) method,the main phenolics of disk were studied.Results: The highest phenolic content was measured in 60% ethanol extraction.The highest content of total flavonoids was measured in 70% acetone extraction.The Jerusalem artichoke disk showed a strong in vitro antioxidant activity by all three methods and liquid phase analysis results,which showed that the quercerin was the main phenolic in Jerusalem artichoke disk.Conclusion: The different extract had great effect on the secondary metabolics content of Jerusalem artichoke disk and the antioxidant activity of disk was strong.