People with substance use disorders often have unhealthy diets, high in sweets and processed foods but low in nutritious items like fruits and vegetables, increasing noncommunicable disease risks. This study investigates healthy eating perceptions and barriers among individuals with opioid use disorder undergoing opioid agonist therapy. Interviews with 14 participants at opioid agonist therapy clinics in Western Norway, using a semi-structured guide and systematic text condensation for analysis, reveal that most participants view their diet as inadequate and express a desire to improve for better health. Barriers to healthy eating included oral health problems, smoking habits, and limited social relations, while economic factors were less of a concern for the participants. Participants did find healthy eating easier when they were in social settings. This study underscores the importance of understanding and addressing these barriers and facilitators to foster healthier eating patterns in this population, potentially enhancing overall health and well-being.© 2024. The Author(s).