We assessed the prevention of hepatic fibrogenesis by a herbal medicine Sho-saiko-to or a carotenoid lycopene in Long-Evans rats with cinnamon coat color (LEC rats). LEC rats were divided into three groups: A (n=40), fed on a basal diet (BD); B (n=25), fed on BD plus 1% Sho-saiko-to; and C (n=40), fed on BD plus 0.005% lycopene. All rats were sacrificed at 76 weeks of age. The liver tissues were stained with Azan--Mallory and alpha-smooth muscle actin (alpha-SMA). The malondialdehyde (MDA) in the liver was measured for the assay of lipoperoxides. The percentage of the total area stained was determined morphometrically. The percentage of the total area involved by fibrosis was 1.35plus minus0.56 in group A, 0.72plus minus0.34 in B (P=0.0020, B vs. A) and 0.78plus minus0.75 in C (P=0.0031, C vs. A). The percentage of the total area that was stained for alpha-SMA was 0.61plus minus0.57 in group A, 0.11plus minus0.05 in B (P=0.0017, B vs. A) and 0.12plus minus0.06 in C (P=0.0021, C vs. A). In group B, MDA in the liver was lower than in group C (P=0.009). In group C, the concentration of iron in the liver was lower than in group A (P=0.0059). In conclusion, Sho-saiko-to suppressed fibrogenesis through reduced generation of lipid peroxides. Hepatic fibrogenesis was also suppressed by lycopene. The mechanisms of this preventive effect of fibrogenesis with Sho-saiko-to and lycopene were suggested to inhibit the stellate cell activity.