Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating condition, characterised by unexplained and excessive fatigue, muscle pain and sleep disturbances. Health anxiety is common in ME/CFS and accurate measurement is essential in facilitating therapeutic gains. However, there are clinical concerns over the utility of the Short Health Anxiety Inventory (SHAI) in measuring health anxiety in this population. This study aims to use qualitative responses from two ex-service users and specialist health clinicians to explore the barriers to completing the SHAI within a specialist ME/CFS service. Qualitative responses from a focus group consisting of 15 specialist health professionals including occupational therapists, physiotherapists, dieticians, cognitive behavioural therapists, counsellors, clinical psychologists and assistant psychologists were transcribed and analysed for themes. Patient voices were represented by two former service users through individual semi-structured interviews on the telephone, which were recorded, transcribed and later analysed thematically. Clinicians and service user involvement agreed on core difficulties with the utility of the SHAI in the ME/CFS population. The timing of the SHAI being administered pre-diagnosis, the language of the SHAI and lack of context around the questionnaire were identified as barriers that were likely to contribute to the SHAI not being completed by service users. Sensitive and accurate measurement is required in order to retain patient engagement, which could further facilitate appropriate assessment and treatment of health anxiety and ME/CFS. Findings suggest that adaption of the SHAI is vital for use with ME/CFS.