Self-efficacy is regarded as a significant factor in self-concept, motivational theories, and healthrelated behaviors, and can seriously influence one's level of performance. The current article seeks to determine the psychometric properties of the Persian version of the General Self-Efficacy Scale (GSES) among substance abusers. Methods: The research method is descriptive and adopts a validation approach. 261 individuals (47 females and 214 males) were selected among the substance abusers who referred to Kermanshah Farabi Therapeutic Educational Center in 2017 in an accessible procedure, and the subjects completed the GSE Scale and AWARE (Advanced WArning of RElapse) Questionnaire-Revised Form. Exploratory and confirmatory factor analysis, Cronbach's alpha coefficient, correlation coefficient, and divergent validity were used for data analysis. Results: The mean and standard deviation of the GSE score of the addicts was 25.79 ± 8.54. The findings corroborated the single-factor structure of the GSE Scale among substance abusers. This factor explained 0.67% of the total variance of the GSE Scale. Cronbach's alpha coefficient was obtained to be 0.94. The results showed that the correlation between the GSE Scale and AWARE Questionnaire was −0.51, and was significant at p < 0.01. Conclusion: Given that the results showed that the GSE Scale has sufficient validity and reliability among substance abusers, it seems that this tool can be used to screen GSE screening among addicts.