To understand hospice palliative care nurses' (HPCNs) perceptions towards spiritual care and their competence to provide spiritual care. Previous research has shown that many nurses lack a clear understanding of the concept of spirituality and feel inadequately prepared to assess patients' spiritual needs. Studies on competence in spiritual care are mostly descriptive, and the evidence for improving it is limited. A mixed-methods research design was used. Quantitative data were collected from 282 nurses in forty hospice palliative care (HPC) institutions in South Korea and analysed using descriptive statistics, independent t-test, one-way ANOVA with Bonferroni test and multiple regression. Qualitative data collection involved two stages: first, an open-ended question posed to 282 nurses, and second, focus group interviews conducted with six HPC experts. Both qualitative data sets were analysed separately using content analysis. This study followed the GRAMMS guidelines. Of the six dimensions of spiritual care competence (SCC), the mean scores were highest in 'attitude towards the patient's spirituality' and 'communication', whereas the 'assessment and implementation of spiritual care' and 'professionalisation and improving the quality of spiritual care' had the lowest mean scores. Through content analysis, 4 themes regarding the meaning of spiritual care, 3 themes regarding requirements for spiritual care and 2 themes regarding preparedness for spiritual care were revealed. They perceived the needs of the understanding of spiritual care based on the attributes of spirituality, the education in systematic assessments and implementation for spiritual care with standardised terminology, and the opportunity to reflect on nurses' own spirituality. Practical SCC training for HPCNs and the subsequent development of clinical practice guidelines are of vital importance. The results of this study provide a useful resource to develop educational programmes for strengthening the SCC of nurses and the entire HPC team.