Background: Recognizing the importance of multidisciplinary collaboration during treatment family conferences is increasing in critical care settings. We aimed to elucidate how critical care specialist nurses engage in the family conference process in terms of the actual discussions held, the recommended topics, and their perspectives regarding transfer of critical care patients to general wards. Methods: This self-administered nationwide survey was conducted between October and December 2020, targeting a random sample of 740 critical care specialist nurses. An anonymous questionnaire based on established guidelines and pilot tests was used to assess the level of engagement with the family conference process, content of discussions, considerations regarding withholding or withdrawing treatment, and perspectives concerning patient care location and discontinuation of life-sustaining treatments among the surveyed nurses. Results: Of the 396 returned questionnaires (response rate, 51.9%), 384 were analyzed. Less than 35% of the nurses consistently participated in family conferences and ensured that decisions regarding withholding or withdrawing life-sustaining treatments were re-evaluated following the conferences. Discussions focused predominantly on the patients’ physical aspects, whereas the nurses believed that patients’ values and preferences should be discussed. More than 70% of the nurses supported transferring patients from critical care settings to general wards for end-of-life scenarios. Conclusions Critical care specialist nurses in Japan exhibit limited engagement in family conferences and often fail to address their patients’ values and preferences. Educational programs and enhanced interprofessional collaborations are warranted to improve nurse involvement in family conferences and ensure continuity of care between critical care and general ward settings.