This study aimed to develop a scale focusing on knowledge and attitudes toward palliative care and end-of-life care for nurses and to confirm the scale's validity and reliability. We conducted a self-administered questionnaire survey with 1745 nurses of 10 hospitals all over Japan. We also examined the test-retest reliability of items for 205 of the nurses, 2 weeks after the first survey was completed. We used item-response theory, factor analysis, and intraclass correlation coefficients. The response rate was 44.5% (n = 762). Ninety items in 9 domains about knowledge of palliative care and end-of-life care were selected by using item-response theory. For knowledge items, Kuder-Richardson-20 was 0.85, and intraclass correlation coefficient was 0.84 in all domains. Ten items in 3 domains about attitudes toward palliative care and end-of-life care were selected by using exploratory factor analysis. For attitude items, Cronbach's α coefficient was .90, and intraclass correlation coefficient was 0.80 in all domains. The developed scale, named the End-of-Life Nursing Education Consortium-Japan Core Quiz, has sufficient validity and reliability. This scale may contribute to assessing the effectiveness of the End-of-Life Nursing Education Consortium-Japan Core Curriculum Nursing Education Program in Japan.