Objective: The present study aimed to investigate the mediating role of cognitive emotion regulation strategies on the relationship between mindfulness, anxiety, and procrastination in high school students. Methods: The study sample consisted of 350 high school female students in Rasht City, Iran. The study subjects responded to the Academic Procrastination Scale (APS), the Cognitive Emotion Regulation Questionnaire (CERQ), the Cattell Anxiety Scale (CAS), and the Five Facet Mindfulness Questionnaire (FFMQ). Data analysis was performed by Pearson product-moment correlation coefficient and structural equation modeling technique in SPSS and AMOS. Bootstrap in Preacher and Hayes’ Macro program (2008) was also used to test the indirect relationships between the study variables. Results: There was a direct and significant relationship between academic procrastination, anxiety, and maladaptive cognitive emotion regulation strategies (P<0.0001). There was an inverse and significant relationship between procrastination, adaptive cognitive emotion regulation strategies, and mindfulness (P<0.0001). Mediation analysis data revealed that the maladaptive cognitive emotion regulation strategies exacerbated the effects of anxiety on academic procrastination; the indirect effect of anxiety on procrastination through adaptive strategies was significant. Conclusion: Procrastination in students could be reduced by minimizing anxiety, correcting maladaptive cognitive emotion regulation strategies, and strengthening adaptive cognitive emotion regulation strategies. Anxiety may aggravate academic procrastination by generating maladaptive mechanisms.