ObjectiveTo describe and analyse emergency nurses' experiences of caring for unidentified patients, and to provide a basis for constructing processes and standards of care for unidentified patients in the emergency department. MethodsThis study is a descriptive phenomenological research that utilized purposive sampling. Sixteen emergency department nurses, who cared for unidentified patients between June and September 2023, were selected for semi-structured face-to-face interviews. Data were analyzed using Colaizzi's 7-step method to identify and refine themes. ResultsThree themes were distilled: (1) increased workload, (2) increased mental stress at work, and (3) material needs and external environmental support. ConclusionEmergency nurses have more complex negative emotional experiences when dealing with unidentified patients and want more external support to cope with such patients. Hospital administrators should pay full attention to nurses' caregiving experiences and provide positive interventions.