Indirect calorimetry was used to study the basal metabolism and energy expenditure at rest in 31 patients aged 20-80 years, on day 2 after surgery on the large intestine. It was found that the basal metabolism was increased by 13% in 64.5% of the patients (group 1) and decreased by the same value in the rest patients (group 2). The fluctuation range of energy expenditure in some patients of group 1 was from 1000 to 3400 kcal, in those of group 2, from 500 to 2000 kcal. The respiratory guotient in both groups was about 0.7. The direct measurement of energy expenditure at the early postoperational period would aid in proper rationing energy components in the total volume of the parenteral nutrition of operated on patients.