Purpose of reviewPolysubstance use, broadly defined as using more than one type of substance, disproportionately impacts those involved in the criminal justice system (CJS). This review synthesizes recent findings on polysubstance use among those involved in the CJS and highlights areas of particular concern and interventions.Recent findingsWe use 18 recent articles to identify the prevalence and types of criminal justice involvement and correlates of polysubstance use and criminal justice involvement. We highlight latent patterns of polysubstance use among various criminal justice populations (adults, pregnant women, and youth) and differential associations with adverse substance use and criminal justice outcomes. Lastly, we discuss substance use treatment in the justice system, the role of polysubstance use in treatment access and outcomes, and substance use-related services for previously incarcerated individuals reentering society.SummaryCurrent research provides further evidence of the syndemic nature of polysubstance use, criminal justice involvement, and adverse outcomes, which are complicated by significant barriers to accessing evidence-based treatment in justice settings. Yet, current research is limited due to methodological inconsistency and limited focus on the social determinants of health, racial/ethnic disparities, and interventions to increase treatment and reentry services.