Background: Back pain (BP) is a major cause of absenteeism in National Health Service (NHS) staff in the UK. However, the back beliefs of NHS staff with BP are unknown. Objectives: To explore the BP beliefs of UK NHS staff presenting with BP, and how these beliefs are constructed. Method: Purposive sampling of NHS staff with BP who had self-referred to University Hospitals of Leicester NHS Trusts occupational health physiotherapy service. 30 participants completed the Back-Pain Attitudes Questionnaire. Ten participants with a range of BP beliefs also completed semi-structured interviews. Mean responses, and frequency of different responses were reported, for the questionnaire data. Interviews were analysed using thematic analysis. Results: Total Back-PAQ scores (mean ¿9.6, SD 9.16) indicated unhelpful BP beliefs overall, though some BP beliefs such as the potential benefit of exercise were more positive. Key themes identified from the interviews were; (i) the uniquely vulnerable nature of BP, (ii) the need to protect the back through avoidance behaviours, and (iii) the importance of being active for BP. Conclusion: NHS staff presenting with BP generally held negative BP beliefs, based on both questionnaire responses and the qualitative interviews. Awareness of the potential benefits of activity contrasted with the notion that ongoing protection of the back was required, and was evident in questionnaire data and interviews. Back pain beliefs were influenced by health care professional advice (both formal and informal settings), moving and handling training, family opinion and childhood experiences, offering insights into the settings where BP beliefs could be targeted.