This study was designed to examine the effect of estrogen deficiency on the metabolism of ethanol in ovariectomized rats. Female rats were assigned to an ovariectomy (OVX) and a sham (SHAM) surgery group. Gain body weight was greater in incresed in OVX group and especially uterus weight significantly decrease depending on the concentration of estrogen after 3 month of ovariectomy. Ethanol at the tolerative dose (6 g/kg) was injected to rats by oral administration to measure the concentration of ethanol in blood. The area under the blood concentration time curve (AUC) was significantly lower in OVX group than SHAM group. The significant decrease in AUC in OVX group indicates that the estrogen deficiency leads to changes of the factors related to ethanol metabolism. Activity of hepatic alcohol dehydrogenase was not significantly influenced by the ovariectomy and also the ethanol elimination rate in vivo was not different. Cytochrome P450 isozymes did not show any changes except CYP 1A1 and 2E1. Level of hepatic glutathione in OVX group was higher after treatment of ethanol. Therefore the reduction of AUC appears not to be directly associated with the difference of ethanol metabolizing enzyme, but to be related with the physical factors like body weight.