The present study was conducted to investigate the effect of different levels of ethanol ingestion on 131ate metabolism and plasma homocysteine concentration in Sprague-Dawley male rats receiving 0, 10, 30% of their caloric intake as ethanol for S weeks. Diets containing 10% ethanol had no effect on plasma and red blood cell(rbc) 131a1e. However, in rats fed a 30% ethanol diet, rbc folate increased and plasma 131ate decreased significantly, In the rats maintained first on a 30% ethanol diet for S weeks and then on a control diet for 2 weeks, the levels of plasma and rbc f31ate were normalized by withdrawal of ethanol. Urinary fo1ate excretion increased markedly in rats fed 10% and 30% ethanol diets and decreased to 51% of controls by withdrawal of ethanol. Plasma homocysteine concentration increased significantly in rats fed a 30% ethanol diet. The results suggest that chronic ingestion of ethanol increased urinary 131ate excretion markedly, which may decrease plasma 131ate and deplete liver folate.