Intermittent Explosive Disorder (IED), characterised by recurrent impulsive aggression, is increasingly linked to violent criminal behaviour (VCB). This systematic review and meta-analysis synthesise evidence on the prevalence, relative risk, and risk/protective factors for VCB among individuals with IED. Key findings revealed a pooled VCB prevalence of 8.9% (95% CI: 5.4-13.2%) in IED populations, escalating to 60-73% in forensic samples. Individuals with IED exhibited a 2.5-fold increased risk of VCB compared to non-IED populations (OR = 2.56, 95% CI: 2.03-3.24), with heightened risk among adolescents and justice-involved subgroups. Adverse childhood experiences, comorbid disorders, and male gender emerged as robust risk factors. Protective factors, though under-explored, included treatment motivation.These findings highlight IED as a critical risk marker for VCB, necessitating tiered interventions targeting trauma, comorbidity, and systemic inequities. This study provides the first comprehensive meta-analytic framework linking IED to VCB, informing clinical and policy strategies to mitigate violence in this population.