Abstract: The aim of this research was to study the chemical constituents and antitumor activity of Swertia mussotii Franch.The ethyl acetate fraction of Swertia was isolated and purified by percolation and various column chromatography,and the chemical composition of Swertia was studied by using physicochemical properties,combining with HR-ESI-MS、¹H NMR and ¹³C NMR;They were named as:1,5,8-Trihydroxy-3-methoxyxanthone (1);1,7-Dihydroxy-3,8-dimethox yxanthone (2);1-Hydroxy-3,5,8-trimethoxyxanthone (3);1-Hydroxy-3,7,8-trimethoxyxanthone (4);4,6,8-Trihydroxy-1,2,3,5-tetramethoxyxanthone (5);Luteolin (6);Isoorientin (7);Isovitexin (8);Swertiamarin (9);Gentiopicroside (10).Compound 5 was isolated from Gentiana plants for the first time,Compounds 6 and 8 were isolated from Swertia mussotii for the first time.The cytotoxic activity of the B16 cell,the glioma C6 cell and the hepatoma HepG2 cell was tested.Finally,the structures of 10 compounds were identified.The results showed that compound 5 has a significant inhibitory activity on the glioma C6 cells with IC₅₀ value at 8.9 μM.

Key words: Swertia mussotii, chemical composition, ethyl acetate fraction, antitumor activity