Abstract: Phytochemical examination of the ethyl acetate extract of root parts of Oroxylum indicum Vent. has led to the isolation of two flavonoid: 2,5-dihydroxy-6,7-dimethoxy flavone and 3,7,3’,5’-tetramethoxy-4-hydroxy flavone by a combination of column and preparative thin layer Chromatography. The structure of these compounds were determined by spectroscopic analysis as well as by comparison of their spectral data with previously reported values. The cytotoxicity of these two compounds and crude petroleum ether, ethyl acetate and methanol extracts was done by brine shrimp lethality bioassay. The LC50 values of compound 1 and 2 and petroleum ether, ethyl acetate and methanol extracts were found to be 14.12, 3.80, 3.97, 6.02 and 8.70 μg/ml, respectively.