Four new triterpene saponins, mandshunosides F-I ( 1–4), together with five known compounds ( 5–9), were isolated from the roots and rhizomes of Clematis mandshurica. Their structures were elucidated on the basis of spectroscopic evidences and hydrolysis products. Bisdesmosidic saponin ( 3–9) showed modest suppression of NO production with the inhibition ratios in the range of 51.3%–64.6% at 50 μmol·L –1, whereas monodesmosidic saponins with a free carboxyl group at C-28 ( 1 and 2) showed potent inhibitory activities with IC 50 values being 12.7 and 8.3 μmol·L –1, respectively.