Twenty-five children aged 2-14 years with isolated and combined craniocerebral injury were examined. Some of them underwent urgent neurosurgical interventions. Mechanical injury and intervention were regarded as aggressive factors. The basic methods were indirect calorimetry and intravenous prolonged glucose and fat tolerance test. The results indicate that in general, the intensity of basal metabolism and the ratio of oxidized energy substrates in children with craniocerebral injury correspond to the course of standard postaggressive reaction. Time course of changes in RQ, structure and share of basic energy substrates in the total energy produced confirm a general biological regularity of postaggressive metabolism: fat is oxidized predominantly during the initial period, while on day 5 inversion of fat and glucose oxidation values is observed.