Diet is a common concern amongst people with an ileostomy as it can be associated with serious and burdensome complications, e.g., dehydration and obstruction, and dietary advice is often unsatisfactory. In this study, we explored healthcare professionals' (HCPs) perspectives on dietary advice for ileostomy management. Semi-structured interviews were conducted with HCPs, from multiple professions, who provide dietary advice to patients with an ileostomy. A Framework approach to thematic analysis was used to understand and compare HCPs experiences, beliefs, and attitudes that influence how dietary advice is provided and effectiveness of dietary management. Findings from interviews with 21 HCPs, across three hospitals, related to seven key themes: tailoring of dietary advice to the patient, patient autonomy and communication, HCP knowledge and understanding, patient pathway, mixed messages, access to formal and social support, and patient understanding and relationship with dietary advice. Profession was a strong determinator of what and how dietary advice is provided; however, closer team working increased consistency of dietary advice. Lack of scientific research and consensus contribute to mixed messages and reduce confidence in dietary advice for people with an ileostomy. Due to individual differences between patients, experiential learning with diet is key to self-management and is encouraged in a controlled way by HCPs; however, a lack of 'one size fits all' guidance can be difficult for some. The study findings should inform HCPs caring for patients with an ileostomy, and researchers designing and evaluating interventions, to improve how patients receive dietary advice for ileostomy management. This article is protected by copyright. All rights reserved.