Twenty-four Oriental herbal medicines including Platycodi Radix and Scutellariae Radix, etc., which have been used for the cure of hyperlipidemia, coronary heart, disease were evaluated for the 3-hydroxy-3-methylglutaryl coenzyme A(HMG-CoA) reductase inhibition and antioxidant effect on a free radical, 1,1-diphenyl-2-picrylhydrazyl(DPPH) in vitro, and antihyperlipidemic effect on hyperlipidemic rats induced by Triton WR-1339 in vivo. 80% MeOH extract of eight herbs including Scutellariae Radix, Coptidis Rhizoma, Paeoniae Radix Rubra, Moutan Cortex Radicis, Angelicae Gigantis Radix, Bambusae Caulis in Taeniam, Cinnamomi Ramulus and Crataegi Fructus inhibited the HMG-CoA reductase activities and exhibited a radical-trapping action on a stable free radical, DPPH. On Triton WR-1339-induced hyperlipidemic rats, four herbs including Scutellariae Radix, Angelicae Gigantis Radix, Bambusae Caulis in Taeniam and Cinnamomi Ramulus showed respectively the significant suppression of serum total cholesterol, triglyceride, phospholipid and LDL-cholesterol levels and serum transaminase(ALT and AST) activities. From these results, it is suggested that each 80% MeOH extract of Scutellariae Radix, Angelicae Gigantis Radix, Bambusae Caulis in Taeniam and Cinnamomi Ramulus have effective antihyperlipidemic action against hyperlipidemia.