Palliative care has the ability to relieve both physical discomfort and psychological distress in terminally ill patients. However, unexpected death may still occur in palliative care settings. This study aimed to utilize Palliative Care Outcomes Collaboration (PCOC) data to better determine any associated factors which may surround unexpected death in palliative care settings. Data were extracted from the PCOC database by the palliative care team within Taichung Veterans General Hospital (TCVGH). Data of deceased patients were extracted during the period from January 2021 to December 2021 from multiple palliative care settings. The deaths of patients whose last recorded palliative phase was 1-3 were defined as unexpected. A total of 280 deceased patients were included, with mean age at death being 67.73, 61% being male, and 83.2% cancer patients. We discovered that shortness of breath, as assessed by the Symptom Assessment Scale (SAS), decreased risk of unexpected death (OR: 0.91, 95% CI: 0.84-0.98), while impending death discharge (OR: 3.93, 95% CI: 1.20-12.94) and a higher Australia-modified Karnofsky performance status (AKPS) score (OR: 1.15, 95% CI: 1.10-1.21) were associated with unexpected death. Thus, medical staff must inform the family of patients early on regarding any risk factors surrounding unexpected death to help everyone involved be prepared in advance.