In choice situations, the golden Syrian hamster shows a strong preference to drink an ethanol solution to water alone. Because of the known effects of ethanol on lipid metabolism, its effects on liver fatty acids were therefore studied in the hamster. After a period of 8 weeks during which hamsters had consumed water containing 10% ethanol (4 weeks) and then 15% ethanol (4 weeks), the liver was significantly increased in weight, an effect which was shown to be due to fat accumulation as triglyceride. The fatty acid composition of the liver triglycerides and phospholipids was altered such that monounsaturated fatty acids were very significantly increased and both n-6 and n-3 essential fatty acids were proportionally decreased.