Objective: The compassionate mind training was designed in accordance with the structure of cognitive-behavioral therapies and the historical period of this therapeutic model is rooted in the improvement of negative emotions in cognitive-behavioral therapy. The aim of this study was to investigate the effectiveness of compassionate mind training in the adjustment of early maladaptive schemas in opiate addicts under methadone maintenance treatment. Method: A quasi-experimental design with pre-test-post-test-follow-up control group design was used in this study. A total of 30 male substance users (mean age = 32.5 years) were selected from two addiction treatment centers by convenience sampling method and were classified into two groups after being diagnosed with axis I disorders through a structured clinical interview. The experimental group participated in twelve sessions of Gilbert's Compassionate Mind Training Group. Participants were evaluated by Yang Primary Schema Questionnaire (short form) in three stages of before intervention, final session, and one month later (follow-up session). Results: The findings of this study indicated that the score of schemas in the experimental group decreased except for the schemes of abandonment/instability, mistrust/abuse, enmeshment, entitlement/grandiosity, and unrelenting standards/hypercriticalness. Conclusion: Based on the results of this study, it can be concluded that the compassionate mind training is an effective treatment in adjusting the early maladaptive schemas among opiate addicts under methadone maintenance treatment.