Three groups of patients were studied by echoencephalography using a one-dimensional encephalograph Eho 12. The first group consisted of 100 patients with a mild craniocerebral traumas. Good pulsations of the elements of the echoencephalogram were found during the study. The second group involved 14 people who had died as a result of craniocerebral trauma. The investigation performed postmortem revealed fixed echoencephalogram without any pulsations of its elements. The third group included 11 patients with severe craniocerebral trauma in a state of deep coma. These patients were on mechanical ventilation, their brainstem reflexes were absent, but the cardiac activity remained preserved. The echoencephalographic study in these patients showed a fixed screen curve, without pulsations of its elements. We conclude that absence of pulsations of the elements of echoencephalogram produced by one-dimensional echoencephalograph indicates brain death of the investigated patients. This investigation should be included as a component of the established diagnostic tests.