Objectives: Spiritual pain is not formally defined. The aim of this study was to clarify the beliefs about spiritual pain among Japanese palliative care physicians and liaison psychiatrists and to compare their beliefs. Methods: A nationwide questionnaire survey was conducted by mail August, 2019 on certified palliative care physicians and liaison psychiatrists. We asked 9 questions about spiritual pain (i.e. current status, definition, and the delivery of care) using a 5-Likert scale. Result: 387 palliative care physicians (response rate, 53%) and 374 psychiatrists (45%) responded. 72% (76% of the palliative care physicians/69% of the psychiatrists) reported that spiritual pain was distinct from depression, but 69% (66/71) reported that it was not defined adequately; and 59% (59/60) perceived the risks of using the words ambiguously. Only 43% (40/47) recommended the universal definition of spiritual pain, and opinions about how spiritual pain should be defined (i.e, higher being, meaning/value, or specific terms) differed among physicians. Perception about spiritual pain of the physicians were significantly associated with their religion, while beliefs about spiritual pain were essentially similar between palliative care physicians and psychiatrists. Conclusion: Although physicians regarded the definition of spiritual pain as being inadequate, the opinions about preferable definition differed among physicians. Discussion about the value of developing a consensus of spiritual pain is needed.