Two flavonoids were isolated from the aerial parts of Salicornia herbacea L. by column chromatography. The structures of the flavonoid compound 1 and 2 were identified as quercetin $3-O-{eta}-D-glucopyranoside$ and isorhamnetin $3-O-{eta}-D-glucopyranoside$, respectively. The antioxidant activity of compound 1 was similar to those of quercetin and rutin, and the activity of compound 2, which contained methoxyl group at flavonoid B-ring, was lower than that of compound 1. The two compounds 1 and 2 were the first to be reported in this plant.