This study aimed to verify the mediating effect of anger expression and anger suppression in the relationship between insecure attachment and marital intimacy. To this end, a self-report survey was conducted targeting married men and women, and SPSS 23.0 and AMOS 23.0 programs were used to analyze the collected data of 374 people. The findings revealed that insecure attachment had a positive correlation with avoidant attachm ent, anger expression, and anger suppression, and a negative correlation with couple closeness. Avoidant attachment had a positive correlation with anger suppression and a negative correlation with couple closeness. Anger expression and anger suppression had a negative correlation with couple closeness. Avoidant attachment did not have a significant correlation with anger expression. Insecure attachment and avoidant attachment had an indirect effect on couple closeness through anger suppression, known as a full mediating effect. On the other hand, anger expression did not show any mediating effect. These findings suggest that suppressing anger, rather than expressing it properly, is importa nt in promoting couple closeness. The study provides important information for interventions that focus on helping couples suppress anger in couples therapy and programs. The study also discussed the limitations and suggestions for future research.