Ethanol causes the accumulation of triglycerides in the liver. Rat liver glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD) are lipogenic enzymes whose activities are positively correlated with the rate of hepatic fatty acid synthesis. The effect of ethanol on fatty acid synthesis in relation to levels of triglycerides in the liver was investigated by assessing activities of hepatic G6PD and 6PGD and levels of hepatic triglycerides in starved rats fed ethanol at a dose of 3 g/㎏ body weight (bw). The acute administration of ethanol caused an increase in triglyceride levels in the liver during 6 h period after the treatment, in which, ethanol caused a 2.2-fold increase in hepatic triglyceride level at 4 h after the ethanol administration. In addition, the time course of serum triglyceride levels was determined. The magnitude and the pattern of changes in serum triglyceride levels in the time course were similar to those in liver triglyceride levels. A single dose of ethanol had no effect at all on activities of lipogenic enzymes G6PD and 6PGD under the condition that caused the triglyceride accumulation in the liver. Taken together, these results suggest that the increase in hepatic triglyceride levels associated with the ethanol ingestion is not likely due to the increase in fatty acid synthesis in the liver.