Introduction. Elder age is a significant negative health factor after traumatic brain injury (TBI). Aim was to study the dynamics of the brain-derived neurotrophic factor (BDNF) level, immune and hormonal disturbances that develop in young and elderly rats during the recovery period after TBI with the correction by recombinant interleukin (IL)-2 (rIL-2). Material and methods. The work was performed on male Wistar rats aged 3 (young) and 18 months (elderly). The «weight drop» model was used as a model for TBI. To correct disturbances caused by TBI animals were medicated with commercial recombinant rIL-2 («Biotech», Russian Federation) in dose of 30 mcg/kg of body weight after the TBI once a day for 3 days. Control animals were injected with 0.15 M NaCl. On days 7 and 14 after TBI, the concentrations of corticosterone, testosterone and BDNF in the blood of animals were determined by ELISA; the activity of immune cells was determined by their cytotoxicity and proliferative activity. Results. In intact and injured animals, both young and elderly, increased concentrations of corticosterone and testosterone were observed after administration of rIL-2 compared to animals not receiving rIL-2. Administration of rIL-2 to intact young and elderly animals did not change the BDNF concentration. TBI led to a significant decrease in BDNF levels in young and old animals, but BDNF levels significantly increased after rIL-2 administration in TBI groups (in both groups p < 0.05). After TBI the proliferative activity of splenocytes in young rats did not decrease, while in elderly rats the inhibition of the proliferative activity of splenocytes was significant (the stimulation index was below one). Administration of rIL-2 did not change the proliferative activity of splenocytes in young intact and injured rats. In elderly animals, a significant increase of suppressed proliferative splenocytes activity after TBI was observed; but in intact animals, the proliferative activity of lymphocytes did not change. TBI led to inhibition of the cytotoxic activity of splenocytes in young and elderly animals; the administration of rIL-2 increased it in injured rats, but did not change it in intact young and elderly rats. Conclusion. rIL-2 in significand degree reversed the posttraumatic changes. Thus, exogenic rIL-2 may to some degree mitigate elder-age-related disfunctions caused and boosted by TBI.