OBJECTIVES: To elucidate changes in depressive symptoms after bereavement and the impact of pre-loss resilience on such changes and on the extent of complicated grief and posttraumatic growth. METHODS: Prospective cohort surveys were provided to family caregivers of patients with cancer in four palliative care units (PCUs) before and after bereavement. Pre-loss Connor-Davidson Resilience Scale scores, pre- and post-loss Patient Health Questionnaire-9 scores, post-loss Brief Grief Questionnaire scores, and the expanded Posttraumatic Growth Inventory scores were determined. RESULTS: Out of 186 bereaved family caregivers, 71 (38.2%) responses were analyzed, among which 47% pre-loss and 15% post-loss responses suggested to be a high risk for major depressive disorder (MDD). Approximately 90% of family caregivers at a high risk for post-loss MDD were already at a high risk for pre-loss MDD. Even after adjustment of the background variables as covariates, the interaction effect between family caregivers' pre-loss depressive symptoms and resilience on post-loss depressive symptoms was observed (F = 7.29; p < 0.01). Moreover, pre-loss resilience was not associated with other bereavement outcome measures. CONCLUSIONS: Among family caregivers of patients with cancer in PCUs, 47% and 15% had high risk for MDD before and after bereavement, respectively. Moreover, pre-loss resilience mitigated post-loss depressive symptoms among family caregivers who had high risk for MDD before bereavement. However, considering the study's small sample size, further research is needed.