Criminal mediation is a major manifestation of restorative justice. It seeks to compensate victims, strengthen offenders’ accountability, reduce tensions caused by crime, and restore social relations. By adopting the 2013 Code of Criminal Procedure and the 2016 Regulation on Mediation in Criminal Matters, the Iranian legislature formally incorporated this institution into the criminal justice system. Using a descriptive-analytical method and drawing on library sources, statutory provisions, judicial decisions, and implementation practices, this study examines the concept, legal foundations, jurisdictional scope, conditions of implementation, and legal and criminological effects of criminal mediation. The findings show that mediation in Iran has moved beyond legislative recognition, yet the full realization of restorative justice remains constrained by divergent judicial interpretations, the financial condition of mediation institutions, limited specialized training, performance-evaluation mechanisms within the judiciary, and differing public attitudes. The comparative analysis indicates that mediation in France first developed within society and was later incorporated into the legal system, whereas in Iran it was introduced mainly through legislation and has acquired a stronger judicial than social life. The study concludes that the principal challenge is not the absence of legal rules but the gap between restorative justice theory and operational realities. Reforming practices, ensuring consistent implementation, strengthening mediator training, supporting mediation institutions, and adopting qualitative evaluation criteria can improve its effectiveness.