This preliminary study examined the self-efficacy of family caregivers with regard to helping cancer patients manage pain at end of life. A sample of 63 family caregivers of hospice-eligible cancer patients with pain provided ratings of their self-efficacy in assisting the patient in pain management and rated their own mood and level of caregiver strain. Patients completed measures of pain and quality of life. Data analyses revealed that caregivers who rated their self-efficacy as high reported much lower levels of caregiver strain as well as decreased negative mood and increased positive mood. Caregiver self-efficacy in managing the patient's pain was related to the patient's physical well-being. In dyads where the caregiver reported high self-efficacy, the patient reported having more energy, feeling less ill, and spending less time in bed. Considered overall, the results of this study suggest that caregiver self-efficacy in pain management is important in understanding how caregivers adjust to the demands of caring for cancer patients who have pain at the end of life.