Abstract: In this study,the leaves of Erigeron breviscapus (Vant)Hand.-Mazz were treated by jasmonic acid on different concentrations,the changes of antiphotooxidation ability,the contents of total flavonoid and chlorophyll were examined.These results suggest that in the third day after treated by jasmonic acid,the content of chlorophyll were examined．These results suggest that in the third day after treated by jasmonic acid,the content total of lavonoid had no obvious change,and it increased significantly in the sixth day.The content of total flavonoid after was treated by 0.5,1.0,1.5mmol/L jasmonic acid were higher than the contrast group,and it was the lowest when was treated by 1.5mmol/L jasmonic acid.The antiphotooxidation ability of E.breviscapus declined when was treated by 0.5mmol/L jasmonic acid,and were increased on 1.0 and 1.5mmol/L concentrations.Although jasmonic acid affected the chlorophyll content of E.breviscapus,it had no effect on the photosynthesis of E.breviscapu.So we can apply exogenous jasmonic acid to artificial planting of E.breviscapus to improve its active compounds content.