Aim: The study aims to examine whether characteristics of patients with Acquired Brain Injury–ABI (time elapsed since injury, level of dependence and behavioral problems) and resilience factors of the caregiver predicted caregiver well-being (quality of life, anxiety,depression and positive aspects of caregiving). Methods: 78 voluntary family caregivers (75.6% female) of patients with ABI completed the Barthel Index, Head Behavior Injury Scale, Questionnaire of Resilience in Caregivers of Acquired Brain Injury, WHOQOL-BREF, Hospital Anxiety and Depression Scale,and Positive Aspects of Caregiving Scale. Correlation analysis and stepwise regression were carried out. Results: Time elapsed since injury showed a negative relationship with positive aspects of caregiving. On the other hand, care-recipients’ behavioral problems showed significant associations with all caregiver variables: negatively with quality of life and positive aspects of caregiving, and positively with anxiety and depression. Regarding resilience, we found a positive relationship with quality of life and positive aspects of caregiving, and a negative association with anxiety and depression, showing better predictive power with depression. Conclusions: We confirm the relevance of developing multidisciplinary caregiver intervention programmes focused on positive ways to handle care-recipients’ behavioral problems and developing positive coping skills, such as positive reinterpretation, acceptance and seeking social support, that may optimize caregiver resilience.