This dataset contains data from an observational study conducted among undergraduate nursing students at a public university in Spain during the 2025–2026 academic year. Data were collected to examine the association between students’ knowledge, attitudes, and practices regarding Advance Care Planning, including Planning Anticipated Decisions and Advance Directives, and their person-centred care orientation in critical health situations. The dataset includes self-administered questionnaire responses covering sociodemographic characteristics and validated scale measures, specifically the PROPAD-pro scale and the Patient–Practitioner Orientation Scale (PPOS). Variables are mainly categorical and ordinal, including Likert-scale items. All data were anonymised, contain no direct identifiers, and were collected using an online questionnaire platform.