© 2018 Alcaraz et al. Purpose: The aim of the present study was to test a structural equation model of patient satisfaction with different key facets of methadone maintenance treatment (MMT). In this model, the three dimensions of patient satisfaction with methadone as a medication (ie, personal functioning and well-being, anti-addictive effect on heroin, and anti-addictive effect on non-opioid substances) were expected to predict satisfaction with the basic interventions delivered by the staff of treatment centers to implement MMT. Patients and methods: A sample of 210 heroin-dependent patients, resistant to MMT treatment (mean age =41.66 years, SD =6.50; 75.7% male), participated voluntarily in this study. Preliminary analysis based on exploratory structural equation modeling supported the expected three-factor measurement model of the scale to assess satisfaction with medications for addiction treatment – methadone for heroin addiction. Moreover, the 15 items measuring staff’s basic interventions were shown to be compatible with the expected single-factor measurement model. Then, both measurement models were included in a structural model. Results: Results of this model show that patient satisfaction with the compatibility of methadone with personal functioning and well-being, as well as with the anti-addictive effects of methadone on non-opioid substances, predicts satisfaction with basic interventions conducted at methadone treatment centers (β=0.191 and β=0.152, respectively). Conclusion: Our results provide further understanding regarding patient satisfaction with MMT, which could help professionals to better understand patient perspective and experience during MMT.