When rats were fed diets containing 10% corn oil for 2 weeks, alpha-glycerophosphate acyltransferase and diacylglycerol acyltransferase levels were reduced to 75% of that of controls fed a 0.5% corn oil diet, while glucose-6-phosphate dehydrogenase, malic enzyme and acetyl-Coa carboxylase levels were reduced to 28, 33 and 66%, respectively. The incorporation of labeled glycerol or palmitic acid into triglycerides by liver slices was also reduced by corn oil feeding. Therefore, it is suggested that although the major reduction of triglyceride synthesis by linoleic acid feeding is due to fatty acid synthesis, glycerolipid synthesis is also reduced.