Abstract: Objective: To examine elevated symptoms on health-related quality of life (HRQOL) measures over 2 years in caregivers of service members with traumatic brain injury (TBI). To compare outcomes to caregivers of veterans. Method: Caregivers (N = 315) were classified into two groups: (a) service member caregiver group (n = 55) and (b) veteran caregiver group (n = 260). Caregivers completed 17 HRQOL measures at a baseline evaluation and follow-up evaluation 24 months later. Results: In the service member caregiver group, the highest frequency of clinically elevated T-scores (≥ 60 T) at baseline and follow-up were found on physical and psychological HRQOL measures (16.4%-30.9%). A higher proportion of the veteran caregiver group had clinically elevated scores on nine measures at baseline and seven measures at follow-up. Examining the number of clinically elevated scores simultaneously across all 17 measures, the service member caregiver group had multiple elevated scores (e.g., 4 or more: baseline = 25.5%, follow-up = 27.3%). A higher proportion of the veteran caregiver group had multiple clinically elevated scores for 13 comparisons at baseline (h = .35-.82), but reduced to eight comparisons at follow-up (h = .36-.63). In the service member caregiver group, the proportion of caregivers with clinically elevated scores at baseline and follow-up was equally dispersed across persistent and newly developed symptoms, but higher for persistent symptoms compared to developed symptoms in the veteran caregiver group. Conclusions: Many caregivers of service members reported clinically elevated scores across HRQOL domains and the prevalence increased over 2 years. More services for caregivers in the Department of Defense may be helpful in reducing the trajectory of newly developed symptoms long term.