Military resilience research is increasing due to the growing literature associating resilience with stress adaptation. The present study aimed to investigate which physiological stress adaptation components were associated with resilience in Special Operation Forces combat service members. Special Operations Forces combat service members (n=117) self-reported resilience (ER89) and self-reported lifetime clinician-confirmed mild traumatic brain injury history. Participants also underwent transcranial Doppler ultrasonography to measure middle cerebral artery velocity during rest and a breath-holding task. Neither resilience nor mild traumatic brain injury history significantly associated with middle cerebral artery velocity percent increase following breath-holding; younger Special Operation Forces combat service members had a higher percent increase in middle cerebral artery velocity following a breath-holding task. Resilience negatively associated with time to return to baseline middle cerebral artery velocity following peak velocity; whereas, mild traumatic brain injury history did not have a significant association. The Special Operation Forces combat service members that scored higher in resilience tended to return to baseline middle cerebral artery velocity following peak velocity faster than their less resilient counterparts. More resilient Special Operation Forces combat service members recovered faster from physiological stress (breath-holding) than less resilient counterparts. This is the first study to investigate resilience and cerebrovascular stress response and recovery in this population. Our initial findings indicated that the Ego Resiliency Scale may be an optimal resilience psychometric and should be used to evaluate effective military resilience trainings, which aim to improve performance and mental health.This article is protected by copyright. All rights reserved.