This study was performed to investigate the hepatotoxicity reducing effect of ethanol extracts from Youngia denticulata Houtt Kitamura (YD) fermented by Aspergillus oryzae, which is well known as a Korean traditional meju microbe. Experimental rats were divided into 4 diets groups (six rats/group) (NC: normal control group, EC: ethanol supplemented control group, ENY: ethanol extracts 0.5% supplemented diets of the non-fermented YD group, EFY: ethanol extracts 0.5% supplemented diets of the fermented YD group). After feeding them for four weeks, the activities GOT and GPT in serum, contents of neutral lipid, total cholesterol, LPO and GSH, and activities of XO (O type) enzyme, SOD and GST in liver tissue were observed. Compared to the NC group, the GOT and GPT activities in the EC group were markedly increased by 87.91% and 57.02%, and the contents of neutral lipid, total cholesterol and LPO were increased by 77.51%, 18.56% and 193.86%, respectively. On the other hand, the GSH content was decreased by 29.52%. The activities of SOD and GST which are anti-oxidation-related enzymes, were decreased by 42.78% and 0.94%, respectively, compared to the NC group, but the XO (O type) enzyme activity was significantly increased by 70.83%. These results confirmed that the liver tissue and anti-oxidation system of the EC group had been damaged. Compared to the EC group, the GOT and GPT activities of the ENY and EFY groups were significantly decreased by 24.73~41.99% and 22.91~30.11%, respectively. The contents of neutral lipid, total cholesterol and LPO were decreased by 16.65~33.33%, 22.44~23.11% and 63.34~66.13%, respectively, but the GSH content was significantly increased by 24.61~35.60%. The GST activity was not significantly affected, but the SOD activity was significantly increased by 214.94~261.19%. The XO (O type) enzyme activity was significantly decreased by 40.34~51.20%. Compared to the ENY group, the GOT and GPT activities of the EFY group were significantly decreased by 22.93% and 9.34%, respectively. The plasma contents of neutral lipid, total cholesterol and LPO were decreased by 20.01%, 0.86% and 7.59%, respectively. The SOD activity was significantly increased by 21.52%, and the XO (O type) enzyme activity was decreased by 18.19%. Given decreasde TG, total cholesterol, LPO contents of liver tissue, GOT, GPT and XO activity, and increased SOD activity, these study results that ethanol extracts from fermented Youngia denticulata Houtt Kitamura may be effective in reducing hepatotoxicity.