The antibacterial components in the roots of Inula racemosa were isolated by various chromatog. methods and elucidated on the basis of spectroscopic data.And their antibacterial activities for Escherichia coli and Staphylococcus aureus were tested.Twelve components were obtained from EtOAc fraction in the ethanol extract from the roots of I. racemosa and identified as dehydrocostus lactone (1), 1α,5αH-13-hydroxyguaia-4(15),10(14),7(11)-trien-6α,12-olide (2), 1α,5α,7α,11H-guaia-4(15),10(14)-dien-6α,12-olide (3), 1α,5α,7αH-3β-hydroxyguaia-4(15),10(14),11(13)-trien-6α,12-olide (4), 1α,5α,7α,11βH-3β-hydroxyguaia-4(15),10(14)-dien-6α,12-olide (5), germacra-1(10),4(5),11(13)-trien-6α,12-olide (6), (E)-3-(4-hydroxyphenyl)-propenoic acid (7), 7-hydroxycoumarin (8), vanillin (9), 3β-hydroxy-5α,8α-epidioxyergosta-6,22-diene (10), β-sitosterol (11), and 1α,5αH-2α,6α-bis-(4-hydroxy-3,5-dihydroxyben)-3,7-dioxabicyclo[3.3.0]-octane (12).Compounds 2-5, 10 and 12 were obtained from the roots of I. racemosa for the first time.Antibacterial activity results of all the compounds showed that compounds 1, 4 and 6 had strong antibacterial activity.