The authors present results of evaluation of immune disorders in 47 patients presenting with brain concussion (BC) and in 28 subjects with mild cerebral contusion (MCC). It was shown that in patients of the former group all immune characteristics were totally restored within 3 weeks after the injury. In the latter group, the clinical picture of secondary immunodeficiency with impaired parameters of the immune status persisted for at least 28 days after the injury. It is concluded that the dynamics of immune system disturbances after a traumatic brain injury may be used as an objective criterion for the evaluation of not only the severity of the injury but also of the duration of the recovery period after mild traumatic brain injury.