One new guaiane-type sesquiterpene glycoside, 2'-O-E-caffeoyl-8alpha-hydroxy-11alpha,13-dihydro-3beta-O-beta-D-glucozaluzanin C (1), was isolated from the whole herb of Ainsliaeafragrans (Compositae), together with five known sesquiterpene lactones: 8alpha-hydroxy-11alpha,13-dihydro-3beta-O-beta-D-glucozaluzanin C (2), 8alpha-hydroxy-11alpha,13-dihydrozaluzanin C (3), 3alpha-hydroxy-11beta,13-dih