: As an intervention for energy malnutrition, frequent meals or a late evening snack (LES) has been recently recommended. On the other hand, it has been reported that glucose intolerance is found in approximately 70% of patients with liver cirrhosis. Thus, we investigated which would be better for the improvement of energy malnutrition and glucose intolerance, treatment with LES alone or LES plus divided meals. : One group of oral supplementation with one pack of a branched-chain amino acid (BCAA)-enriched nutrient, Aminoleban EN (210kcal), at 10 p.m. LES and the other group with two packs of Aminoleban EN (one pack at 10 p.m. as LES and another pack during the day, i.e. at sometime from 10 a.m. to 3 p.m.) were examined to determine the influence of LES on the blood glucose level, biochemical parameters, and energy metabolism. Twenty-six patients participated in this study. The administration period was 7 days. Metabolic measurements were performed using an indirect calorimeter. : The fat oxidation rate was significantly decreased and the carbohydrate oxidation rate significantly increased in both groups. As a result, respiratory quotient (RQ) was significantly improved. In many cases, the increase of the glucose level after meals seemed to be reduced after LES administration for 1 week. LES could improve energy malnutrition, and correct amino acid imbalance. There was also a significant correlation between non-protein respiratory quotient (npRQ) and the creatinine height index. : LES alone improved the energy malnutrition state and glucose intolerance equivalent to LES plus divided meals. Thus, LES may improve glucose intolerance in patients with liver cirrhosis.