Introduction: The aim of this study was to investigate the effectiveness of cognitive-behavioral group therapy on divorced women’s emotional regulation and meta-cognitive beliefs and rumination. 
Materials and Methods: The study population of this clinical trial includes all divorced women referred Sanjesh-e Danesh o Aramesh counseling center in Mashhad in the 2nd quarter of 2015. The sample size includes 30 divorced women who were selected through convenience sampling and then attributed randomly in two groups, 15 as control group and 15 as experimental group. The experimental group was treated with 12 sessions of cognitive-behavioral group therapy. There was no intervention for control group. Garnovski's Cognitive Emotion Regulation Questionnaire (CERQ 36), Meta-Cognitive Beliefs Questionnaire (MCBQ 30), and Ruminative Response Scale (RRS-22) were used to evaluate pretest and posttest status. Data analysis was performed through MANCOVA and univariate covariance analysis by SPSS software version 21.
Results:The results of MANCOVA test showed a significant difference between the study groups in dependent variables. In order to determine which dependent variable shows significant difference among groups, univariate covariance analysis was used, which showed a significant difference in all dependent variables among groups (P<0.005).
Conclusion: Based on the results, we can conclude that cognitive-behavioral group therapy influences emotional regulation, meta-cognitive beliefs, and rumination.  Hence, this method is effective and useful in alleviating symptoms affecting women after divorce and to sustain and improve their mental health.