Objectives: The main goal of end-of-life care is to achieve the best quality of life (QOL) for patients. The purpose of this study was to investigate the impact of (1) the patients' awareness of their prognosis, (2) the extent of patient-family caregiver congruence on the preferences for end-of-life care options, and (3) the perceived caregiving burden of family caregivers when they provide end-of-life care to their dying relative, on the QOL for terminally ill cancer patients in Taiwan. Methods: A total of 1108 dyads of patient-family caregiver from 24 hospitals throughout Taiwan were one-time surveyed. Predictors of the QOL were identified by multiple regression analysis. Results: Controlling for the effects of age, financial status, and symptom distress, a novel finding of this study was that the patient awareness of prognosis, patient-family caregiver congruence on the preferred place of death, and the subjective family caregiving burden had a significant impact on the QOL of Taiwanese terminally ill cancer patients. Conclusions: QOL is not only related to the unavoidable decline in physical condition and daily functioning of the dying patient but is also related to domains that, as death approaches, have the potential to show improvement through the efforts of health-care professionals, such as presenting prognostic information to optimize the patients' understanding and assists them with psychological adjustments, facilitating patient-family caregiver congruence on the end-of-life care decision regarding the place of death and lightening the caregiving burden of family caregivers.