Aims: Anger rumination is a recurring cognitive process and is one of the internal manifestations of anger that leads to increased and persistent anger in individuals. The aim of this study was to investigate the relationship between emotion regulation and mindfulness with the ruminant anger of perpetrators of violent crimes.

Materials & Methods: The present study is descriptive and correlational. The statistical population included all male prisoners prisoners aged 18-50 in Ahvaz in 1396 who had committed violent crimes (256 people), of which 150 were selected by available sampling method. Data collection tools were Freiburg's Mindfulness Questionnaires, Cognitive Emotion Search, and Anger. Following the issuance of the necessary permits and the consent of the prison authorities, the objectives of the investigation were presented to all participants and the questionnaires were distributed by the prison staff. Data analysis was performed using Pearson correlation matrix and step-by-step regression analysis in SPSS 26 software.

Findings: The age range of the 150 men in the study who committed violent crimes ranged from 18 to over 50 (average 36 years). The results of the correlation coefficient showed that there was a significant correlation between negative emotion regulation strategies and significant negative correlation (p<0.05) and negative anger regulation strategies with anger ruminants (p<0.01). Also, positive emotion regulation strategies were positively and significantly correlated with mindfulness (p<0.01). Although there was a negative relationship between positive emotion regulation strategies and anger rumination, this relationship was not significant. The results of regression analysis also showed that negative emotion regulation strategies could significantly predict rumination.

Conclusion: The results of this study show the importance and necessity of paying attention to rumination as an effective factor in violent crimes. Identifying this psychological structure can be considered an important step in preventing violent crimes.