OBJECTIVES: Behavioral health needs are highly prevalent among individuals receiving long-term services and supports (LTSS), yet palliative care (PC) models in these settings often underemphasize psychiatric symptom management. This study explores interdisciplinary staff perspectives on behavioral health as a core domain of PC across nursing home and Program of All-Inclusive Care for the Elderly (PACE) sites. METHODS: We conducted a secondary analysis of a multi-site survey assessing PC needs across 13 LTSS sites within a large health system in New York State. We examined 5 survey items related to psychiatric symptom management, analyzing frequency, comfort, perceived benefit, and training interest. Multivariable logistic regression was used to assess associations between staff characteristics and behavioral health-related outcomes. RESULTS: Among 597 respondents, 60.5% reported that over half of their patients could benefit from psychiatric symptom management, and nearly half (49.2%) reported managing such symptoms weekly or more. Forty percent identified psychiatric symptom management as one of the top three ways PC specialists could help their patients, and 44.6% expressed interest in further behavioral health training as part of further PC training. Prior professional experience with PC was associated with greater recognition of behavioral health needs among patients (aOR 1.6), greater likelihood of managing psychiatric symptoms (aOR 2.0), and greater comfort doing so (aOR 1.5). SIGNIFICANCE OF RESULTS: Behavioral health emerged as a salient and frequently encountered domain of serious illness care among LTSS staff, particularly in nursing home and PACE settings. Staff with prior PC experience were more engaged and confident in addressing psychiatric symptoms. Findings underscore the need for PC models in LTSS to better integrate behavioral health - through training, interdisciplinary collaboration, and care delivery redesign - to meet the complex needs of medically and psychiatrically vulnerable populations.