Abstract: Objective: To examine (a) change in chronic neurobehavioral symptoms in service members/veterans (SMVs) with an uncomplicated mild traumatic brain injury (MTBI) at two time points over 3 years and (b) the influence of intimate partner (IP) health-related quality of life (HRQOL) risk factors for chronic neurobehavioral symptoms. Method: IPs (N = 175) completed measures of SMV neurobehavioral adjustment symptoms and 13 IP HRQOL risk factors at Time 1 (T1) ≥ 12 months post-TBI and Time 2 (T2) 3 years later. Scores on the risk factor measures were classified into four IP HRQOL symptom trajectory categories based on clinically elevated (≥ 60 T) symptoms: (a) persistent (T1 + T2 ≥ 60T), (b) developed (T1 < 60T + T2 ≥ 60T), (c) improved (T1 ≥ 60T + T2 < 60T), and (4) asymptomatic (T1 + T2 < 60T). Results: There was little change in mean SMV adjustment scores or the percentage of clinically elevated scores from T1 to T2. The percentage of clinically elevated adjustment scores was 30% at T1 and T2; 14.3% at T1 only; and 5.7% at T2 only. The IP HRQOL symptom trajectories had a stronger effect on mean SMV adjustment than within-group change in adjustment, which was largely driven by the persistent and asymptomatic IP HRQOL categories. The strongest effects were found for caregiving and social HRQOL risk factors, followed by psychological, and then physical HRQOL risk factors. Conclusion: A range of clinically elevated IP HRQOL constructs emerged as long-term risk factors for chronic neurobehavioral symptoms in SMVs post-MTBI. More attention to the role that family distress has on poor warfighter recovery and return to duty following an MTBI is required.