Objective To study the chemical constituents of Swertia decora, a traditional herb used to treat hepatitis by the minority.Methods The constituents were separated and purified by column chromatography with silica gel.Their structures were identified on the basis of spectral analysis such as UV, MS, NMR, HMPC, HMQC and by HPLC.Results Three compounds were isolated from the chloroform part and ethyl acetate part of the extracts.Their structures were identified as 1-hydroxy-4, 5, 6, 7-tetra- methoxy -9H-xanthen-9-one (swertiadecoraxanthone-Ⅰ, Ⅰ), 5, 7, 3′, 4′- tetrahydroxyflavone (luteolin, Ⅱ), and 3, 5, 7, 3′, 4′-pentahydroxyflavone (quercetin, Ⅲ), respectively.Conclusion Swertiadecora- xanthone -Ⅰ is a new compound and the other two are found from this plant for the first time.The pentaoxygenated patterns of compound Ⅰ is also found for the first time in the plants of Swertia L.