This study clarified the evaluation of the information about palliative care units (PCUs) from the oncologists by the bereaved family members of Japanese patients with cancer at the time of their first referral. A multicenter questionnaire survey examining the amount, timing, and adequacy of information received about PCUs was conducted. Half of the respondents (N = 465, mean age = 60 years) were spouses. Findings showed that 55% of the respondents thought the amount of information was inadequate and 33% thought the timing of the information about PCU from the oncologist was inadequate. Greater perceived inadequacy of the amount of information was significantly associated with (1) obtaining information from other patients and/or family member who had no experience with PCUs and (2) not acquiring information about the availability of medical staff and medical treatments at PCUs. Greater perceived inadequacy of the timing of the information was significantly associated with acts by the oncologist and/or nurses, such as providing insufficient information or saying there is nothing more that can be done any longer; however, this was not significantly associated with the actual timing of the oncologists’ information. Medical staff should understand what information families desire and provide enough detail for patients to imagine accurately what time spent in a PCU would be like. Moreover, practitioners should strive to improve methods of communication and engagement after the information provision, rather than prioritizing the timing of the information.