The present study set out to examine the effectiveness of the Children of Divorce Intervention Program (CODIP) on emotional regulation and psychological well-being among children of divorce in schools in Sari. This quasi-experimental study used a pretest–posttest design with a control group. The statistical population included all 8- to 10-year-old students from divorced families in Sari, from among 30 participants were purposively selected based on inclusion criteria and randomly assigned to experimental and control groups. Data were collected using the Emotion Regulation Questionnaire (Zeman et al., 2002) and the Psychological Well-Being Scale (Opree et al., 2018) at both pretest and posttest stages. The experimental group received 15 weekly CODIP sessions (45 minutes each), while the control group received no intervention. Data were analyzed using multivariate analysis of covariance (MANCOVA) in SPSS version 23. The results demonstrated that CODIP had a significant effect on improving emotional regulation (p ≤ 0.001), but no significant effect on enhancing psychological well-being (p = 0.081). The effect size index indicated that 66% of the variance in emotional regulation scores was attributable to the intervention. Based on these findings, CODIP can be considered an effective preventive and supportive approach for improving emotional regulation in students facing psychological challenges resulting from parental divorce.