Ying-Zai Chen,1 Wei-Lieh Huang,1,2,5 Jia-Chi Shan,4,5 Yu-Hsuan Lin,1–3,5 Hung-Chieh Wu Chang,1 Li-Ren Chang1,61Department of Psychiatry, National Taiwan University Hospital, Yun-Lin Branch, 2Institute of Brain Science, National Yang-Ming University, 3Sleep Research Center, National Yang-Ming University, 4Department of Psychiatry, Cathay General Hospital, Taipei, 5Department of Psychiatry, National Taiwan University Hospital, 6Department of Psychiatry, Medical College, National Taiwan University, Taipei, TaiwanBackground: Health-related quality of life (HRQoL) remains poor among heroin users, even after being treated with methadone. Evidence regarding self-reported psychopathology and HRQoL in heroin users is also limited. The present study aimed to investigate the association between self-reported psychopathology and HRQoL in Asian heroin users treated with methadone.Methods: Thirty-nine heroin users treated with methadone and 39 healthy controls were recruited. Both groups self-reported on demographic data, the Brief Symptom Rating Scale, EuroQoL-5D, and World Health Organization Questionnaire on Quality of Life: Short Form. We compared clinical characteristics, psychopathology, and HRQoL between the two study groups. Correlation and regression analyses were conducted to explore the association between psychopathology and HRQoL in the heroin user group.Results: Heroin users had more psychopathology and worse HRQoL than healthy controls. The HRQoL of heroin users had significant correlations with Brief Symptom Rating Scale scores. HRQoL could be predicted by depression, anxiety, paranoia, and additional symptoms (ie, poor appetite and sleep difficulties) independently.Conclusion: Self-reported psychopathology, depression, anxiety, paranoia, poor appetite, and sleep difficulties had a negative impact on each domain of HRQoL among heroin users treated with methadone. The importance of the environmental domain of HRQoL is discussed. Clinicians should recognize comorbid psychiatric symptoms early on to improve HRQoL in heroin users.Keywords: heroin abuse, Brief Symptom Rating Scale, World Health Organization questionnaire on quality of life