Alcoholic extracts from bark of Calocedrus macrolepis var. formosana Florin (Cupressaceae) were extracted successively using n-hexane, dichloromethane, ethyl acetate, 1-butanol and water, which gave 34.8%, 34.1%, 24.1%, 3.3% and 3.7% soluble fractions, respectively. Antioxidation activity of these fractions by DPPH assay and dissimilar IC50 values of the DPPH showed that ethyl acetate fraction had the best antioxidant activity; its IC50 was 2.6 mu g/ml. Analyses of the composition and anti-inflammatory activity of the subfractions from n-C6H14 fraction showed that the T3 and H5(ppt) had the best anti-inflammatory activity in LPS-stimulated murine macrophage J774A. 1 cells, respectively; moreover, their major constituent was sugiol (T3 37.1%, H5(ppt) 81.1%), which at dosages of 10 mu g/ml inhibited proIL-1 beta protein production completely. Furthermore, the T1 also exhibited anti-inflammatory activity, and its major constituent was ferruginol (above 85.6%). (c) 2005 Elsevier Ltd. All rights reserved.