This article describes the whole picture of Japan HOspice and Palliative Care Evaluation Study 3 (J-HOPE3 Study) including study design and demographic data. The aims of the J-HOPE3 study were to (1) evaluate the process, structure, and outcome of palliative care in the following care settings: acute hospitals, inpatient hospice/palliative care units (PCUs), and home hospice services; (2) examine bereaved family members’ self-reported psychosocial conditions, such as grief and depression, as bereavement outcomes; (3) provide data to ensure and improve the quality of care provided by participating institutions through feedback concerning results for each institution; and (4) perform additional studies to explore specific clinical research questions. We conducted a cross-sectional, anonymous, self-report questionnaire survey involving patients’ bereaved family members in 20 acute hospitals, 133 PCUs, and 22 home hospice services between May and July 2014. Two types of questionnaires were used: main and specific studies questionnaires. The questionnaire was sent to totally 13 584, and 10 157 returned the questionnaire. The analysis included 9126 family members’ questionnaires from acute hospitals, PCUs, and home hospice services. Respondents’ average age was 61.6 years, 55% were women, and 40% had been married to the deceased. With respect to the characteristics of participating institutions, most institutions did not have religious affiliations, and most PCUs and home hospice services provided bereavement care. These results of the analysis of common and additional questionnaires could play an important role in clinical settings, quality improvement, research, and public accountability.