Abstract Caregivers of patients with hematologic malignancies undergoing hematopoietic stem cell transplantation (HSCT) must cope with substantial caregiving burden, high rates of psychological distress, and diminished quality of life (QOL). However, data describing coping strategies before HSCT and the association between coping, QOL, and psychological outcomes in this population are lacking. We conducted a secondary analysis of data collected during a multisite randomized clinical trial of a supportive care intervention in HSCT recipients and their caregivers. Caregivers completed the Brief COPE, Hospital Anxiety and Depression Scale, and the Caregiver Oncology Quality of Life Questionnaire to measure coping strategies, psychological distress, and QOL, respectively. We grouped coping into 2 higher-order domains: approach-oriented (ie, emotional support and active coping) and avoidant (ie, self-blame and denial). We used the median split method to describe the distribution of coping and multivariate linear regression models to assess the relationship between coping and caregiver outcomes. We enrolled 170 caregivers, with a median (range) age of 53 (47-64) years. Most were White (87%), non-Hispanic (96%), and female (77%). Approach-oriented coping was associated with less anxiety (β = −0.210, P = .003), depression symptoms (β = −0.160, P = .009), and better QOL (β = 0.526, P = .002). In contrast, avoidant coping was associated with more anxiety (β = 0.687, P<.001), depression symptoms (β = 0.579, P < .001), and worse QOL (β = −1.631, P < .001). Our findings suggest that coping is related to distress and QOL among caregivers of HSCT recipients even before transplant. Hence, caregivers of patients with hematologic malignancies undergoing HSCT may benefit from resources that facilitate adaptive coping with the demands of caregiving.