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Introduction: Addiction is a chronic and progressive disease that is associated with dysfunction and changes in the function of the nervous system. Novel advances in non-invasive brain stimulation techniques open a new horizon in this field. The aim of this study was to investigate the effect of transcranial direct current stimulation (tDCS) on reducing craving in people with substance use disorder. Materials and Methods: The present study was a meta-analysis. The statistical population of the study included master's and doctoral theses, studies published in scientific and research journals, and research indexed by Iranian writers abroad. After stipulating the inclusion and exclusion criteria, interventions based on tDCS on craving in people with substance use disorder between 2011 and 2021 were selected from databases, and among them, 18 studies with 31 effect sizes were selected for final analysis. The steps of the meta-analysis were based on Howitt and Kramer Meta-Analysis Method (2005). Results: The results showed that the obtained effect size was 0.74. The combined significance level of the studies was obtained, indicating that the total effect size of tDCS studies was significant in the regulation of craving in people with substance use disorder. Conclusion: The results showed that the effect size of interventions based on the treatment of tDCS on reducing drug craving is high based on Cohen's interpretation table. Therefore, applying this new therapeutic approach, as an effective method in reducing craving, can improve the performance of people with substance use disorder.