To study the flavonoids of Scutellaria baicalensis and their bioactivities.Chromatographic methods were used to separate compounds, spectral methods were used to determine the structures and bioactivities of the flavonoids were screened in several models in vitro.Nine compounds were isolated and identified as baicalein (1), wogonin (2), oroxylin A (3), 5, 7, 2', 6'-tetrahydroxyflavone (4), viscidulin III (5), baicalin (6), wogonoside (7), oroxylin A-7-O-beta-D-glucuronide (8) and chrysin-6-C-alpha-L-arabinopyranosyl-8-C-beta-D-glucopyranoside (9).Baicalein had good anti-bacteria activity, and some compounds showed inhibiting activity against IL-1beta converting enzyme. The 13C NMR data of compounds 9 were assigned correctly by 2D nuclear magnetic resonance (NMR).