Social workers in substance abuse treatment settings are responsible for involving families in treatment program to improve family functioning. The effectiveness of available interventions in treating codependency of family members of drug users in Iran is not well explored. We evaluated the effectiveness of the Satir communication family therapy (CFT) in healing codependency of drug dependents' family members in Tehran, Iran.The intervention group participants (n = 27) received a seven-session social work intervention with CFT approach and the control group (n = 26) received treatment as usual. We used the Holyoake Codependency Index to measure participants' codependency at baselines, end of intervention, and 90 days post intervention.Codependents enrolled in the intervention had a significantly lower codependency score than controls at the end of intervention and 90 days post intervention.CFT is an effective strategy to reduce codependency in Iranian population and can be explored as a population-based strategy.