Background <p>Diabetes mellitus in children, adolescents and young adults presents major clinical, social, and psychological challenges, particularly in low- and middle-income settings. Despite donor-supported access to free insulin and self-management supplies, many youths continue to have poor glycemic control. This study assessed barriers to glycemic control among Ghanaian youth with Type 1 and Type 2 diabetes, focusing on sociodemographic factors, institutional and family support, and stigma.</p> Methods <p>A convergent cross-sectional mixed-methods study was conducted among 161 participants under 30 years attending a pediatric and adolescent endocrine clinic in Ghana between July and December 2025. Quantitative and qualitative data were collected concurrently through structured interviews containing closed-ended and open-ended questions. Quantitative data assessed socioeconomic barriers, institutional support, stigma, and disclosure patterns, while qualitative data explored participants’ experiences and perceptions of diabetes-related stigma. Clinical data, including diabetes type and HbA1c measured using an Abbott Afinion™ 2 point-of-care analyzer, were extracted from medical records. Quantitative data were analyzed descriptively and using ordinal logistic regression, while qualitative responses were analyzed thematically. Findings were integrated during interpretation using the socioecological framework.</p> Results <p>Most participants were adolescents or young adults (88.8%), and 81% had Type 1 diabetes. Glycemic control was poor (mean HbA1c 9.97% ± 2.5%), with 85% of participants having HbA1c above 7.5%. Although most participants had access to free insulin, 30% reported difficulty affording transportation to clinic visits, and 24% experienced food insecurity. Institutional support was limited, with only 15.4% having access to a health professional and 25% to a school/work health facility. Stigma was widespread, with 72% perceiving diabetes as stigmatized in their communities. Qualitative findings highlighted fear of disclosure, social exclusion, and misconceptions such as diabetes being contagious or spiritually caused, which contributed to concealment and avoidance of social activities (reported by 43%). Only 28% of participants had disclosed their diagnosis beyond close family and friends. Socioeconomic status was the most consistent predictor of glycemic control, with higher status associated with lower odds of poor control. Integration of quantitative and qualitative findings demonstrated that socioeconomic disadvantage, institutional limitations, and stigma jointly impacted diabetes self-management behaviors.</p> Conclusions <p>Beyond insulin access, Ghanaian youth with diabetes face significant socioeconomic and psychosocial barriers. Improving outcomes requires integrated interventions, including targeted financial support, strengthened institutional care, and stigma reduction.</p> Clinical trial number <p>Not applicable.</p>