Abstract: A new lignan, tirpitzin A ( 17 ) together with 20 known compounds ( 1-16 , and 18-21 ) were isolated from the ethyl acetate soluble fraction of ethanol extract of the aerial parts of Tirpitzia ovoidea. The structure of new compound was elucidated by means of spectroscopic analysis. Of the known compounds, 7-21 were isolated from Linaceae family for the first time. The pharmacological activity of the crude extracts was tested using a mouse inflammation model induced by dimethyl benzene. The results demonstrated that the ethyl acetate soluble fraction had anti-inflammatory activity. Moreover, the cytotoxic and anti-inflammatory activities of some compounds were studied. The new compound 17 showed moderate cytotoxic effect against BxPC-3 cell line (IC₅₀=19.51μmol·L^-1) and Compound 10 showed significant cytotoxicity against HepG2, HL-60, U87 and BxPC-3 cell lines with IC₅₀ values in the range 4.2-8.3μmol·L^-1. Additionally, Compounds 2 , 10 , 11 , and 13 exhibited potent inhibitory effects on LPS-induced nitric oxide production in RAW 264.7 macrophages at the concentration of 50μmol·L^-1.