Background Family caregivers of patients with advanced cancer have been reported to provide long hours of care and be at risk for poor psychological outcomes. Although research has focused on the nature of caregiving burden, little attention has been paid to identifying protective factors that improve caregiver psychological outcomes. Aim We examined the relationship between caregivers' time spent caregiving and the following psychological outcomes: anxiety, depression and caregiving esteem. Subsequently, we explored the main and moderating effects of caregiver-perceived self-competency and sense of meaning on caregiver psychological outcomes. Design/participants Cross-sectional analysis was conducted using the baseline data from an ongoing cohort study. Family caregivers of advanced cancer patients (n=287) were recruited from two tertiary hospitals in Singapore. Results Time spent caregiving was not significantly associated with caregiver anxiety, depression or caregiving esteem. However, significant main effects of self-competency on anxiety and caregiving esteem; and sense of meaning on anxiety, depression and caregiving esteem were observed. Moderator analyses further indicated that self-competency attenuated the positive relationship between time spent caregiving and anxiety, while sense of meaning attenuated the negative relationship between time spent caregiving and caregiving esteem. Conclusion Greater perceived self-competency and sense of meaning are related to better caregiver psychological outcomes, and protect caregivers from worsening outcomes as caregiving hours increase. Our findings suggest that screening caregivers for distress is an important part of care, and that supportive interventions for caregivers should aim to enhance their perceived caregiving competencies and the ability to make meaning of their caregiving role.