Adolescence, a critical period of physical and psychological development, presents unique challenges in type 1 diabetes (T1D) management due to endocrinological changes, reduced therapeutic adherence, and elevated susceptibility to psychological issues such as depression, anxiety, and eating disorders. This narrative review explores the impact of psychological and behavioral factors on glycemic control in adolescents with T1D. We examine the prevalence and influence of mental health disorders, lifestyle factors, harmful behaviors, and social dynamics on diabetes management and glycemic outcomes. Strategies for improving metabolic control are also reviewed, including cognitive behavioral therapy, technological devices, and educational interventions. The importance of tailored psychological support, family involvement, and targeted interventions to improve adherence to treatment and glycemic control in adolescents with T1D should be emphasized.