Aim: The present study aims to determine the effect of a stress-management training program on the readiness for substance use treatment, based on health belief model (HBM). Method: In this quasi-experimental study, which was conducted in 2013, a number of 85 male substance users in Hamadan were enrolled in the study. The data collection tools were Perceived Stress Scale, Self-efficacy Scale, Stages of Change Readiness, Treatment Eagerness Scale, and questionnaire based on HBM. The intervention was an educational program including five sessions during 5 weeks included nature of stress and stress-management practices. A pre and posttest were performed over a period of 2 months before and after intervention. Analytical and descriptive tests were used for data analysis, at 95% significant level, using Statistical Package for the Social Sciences 16. Results: After the intervention, the mean score of perceived stress decreased to 26.38 in the intervention group, whereas in control group, it remained relatively unchanged (49.19), (P < 0.05). A significant difference was found in HBM constructs in the intervention group, comparing to the control group after educational interventions (P < 0.05). Conclusion: Stress-management training based on HBM might be effective in promoting readiness for substance use treatment.