This study identifies institutional, financial, and sociocultural barriers limiting STI testing and treatment for incarcerated U.S. youth. Stigma, health care mistrust, poor infrastructure, and systemic neglect disproportionately harm marginalized groups, especially Black, Hispanic, and Indigenous juveniles. Findings stress the need for confidential, culturally competent, trauma-informed care; policy reforms prioritizing rehabilitation over punishment; and targeted interventions to reduce STI disparities.