To evaluate the effect of ethanol pretreatment on the liver and serum xanthine oxidase(XO) activity, the bromobenzene(40mg/kg body wt., i.p.) was orally given 3 times daily to the Sprague-Dawley male rats pretreated with 5% ethanol throughout 2 months. Bromobenzene treated rats pretreated with ethanol showed the more decreased activity of serum and liver XO, and lower value of V than those of only bromobenzene treated rats. Bu the bromobenzene treatment, ethanol pretreated rats showed the more decreased levels of serum alanine aminotransferase activity and liver weight/bo여 weight(%), and decreased degree of liver damage on histopathological observation than the control group.