Background: Informing families of a patient's death is one of the most challenging responsibilities of clinicians who provide care for terminally ill patients. Although death pronouncement can be a highly stressful event for clinicians, no previous study has reported qualitative characteristics of the burden experienced by clinicians related to death pronouncements. Moreover, no scale has been developed to assess this burden. Objective: This study sought to develop a scale to evaluate clinicians' burden related to death pronouncement (Death Pronouncement Burden Scale for oncology practice [DPBS-oncol]) and examine its reliability and validity in Japan. Methods: We presented the DPBS-oncol to clinicians involved in oncology practice and examined its reliability and discriminant validity. To investigate the test-retest reliability of the scale, the DPBS-oncol was presented a second time to a subsample of the clinicians. Results: Factor analysis required a grouping of the 15 DPBS-oncol items into one factor. Cronbach's α coefficient of the total score of DPBS-oncol was 0.94, and the intraclass correlation coefficient of the total score of DPBS-oncol was 0.89. Regarding discriminant validity, DPBS-oncol total score was moderately correlated with other available scales for assessing clinicians' attitudes to end-of-life care. Conclusion: This study was the first to develop a scale to evaluate clinicians' burden related to death pronouncement. The DPBS-oncol, which includes 15 items, was validated and shown to have sufficient reliability.