Soft corals belonging to the genus Nephthea have been found to be a rich source of terpenoids and steroids. Chromatographic separation of acetone and CH2Cl2/MeOH extracts of Formosan soft coral Nephthea chabrolii resulted in the isolation of thirteen new steroids, including nine 4£\-methylated steroids (1−6, 8−10), three 19-oxygenated steroids (11−13), and a novel skeleton 19-norsteroid (7). The structures of these metabolites were elucidated by extensive spectral analyses and anti-inflammatory activities were measured in vitro. Compounds 1−2, 4−5, 7−11 and 13 at a concentration of 10 £gM significantly reduce the levels of iNOS (inducible nitric oxide synthase ). Compounds 2, 4, 6−7 and 10−11 at a concentration of 10 £gM also significantly reduce the levels of COX-2 (cyclooxygenase-2). Compounds 2, 4, 7, 10 and 11 can reduce the levels of both iNOS and COX-2. All compounds at a concentration of 10 £gM did not affect the housekeeping £]-actin protein expression.