Background: Patients with non-cancer disease are less likely to receive specialized palliative care than cancer patients. To be able to provide the best specialized palliative care, it is important to understand palliative care needs of non-cancer patients and whether the type and level of needs differ from those of cancer patients. Large studies including both cancer and non-cancer patients, using validated needs-assessment-tools, are needed to understand differences in palliative care needs at admittance to specialized palliative care. Aims: To compare palliative care needs at the start of palliative care for cancer and non-cancer disease. Design: Six-year nationwide register-based study. Setting/participants: This study included patients from all Danish specialized palliative care services (hospice care, hospital-based palliative care, home-based palliative care, or consultation) who completed a need-assessment-questionnaire. Ordinal logistic regression was performed to study the association between diagnosis and needs. Results: Cancer patients had a higher probability of receiving specialized palliative care. Of the 44,315 palliative care admissions included in this study, 93.3% were on cancer patients. Independent of diagnosis patients experienced on average six needs and high levels of fatigue and impaired physical functioning. Non-cancer patients had significantly higher odds of insomnia, fatigue and impaired emotional functioning, physical functioning, and quality of life whereas cancer patients had higher odds of pain (except for patients with neurological disease). Conclusions: The higher levels of several symptoms/problems among non-cancer patients compared to cancer patients suggests that referral to specialized palliative care should be improved for non-cancer patients perhaps by improving identification of palliative needs.