Diabetic adolescents have poor metabolic control. We aimed to characterize the longitudinal association between the stress-related domains of emotional burden (EB), physician related-distress (PD), regimen-related distress (RD), diabetes-related interpersonal distress (ID), and hemoglobin glycosylated (HbA(1c)) trajectories among Type 1 diabetics Chilean adolescents. Thirty-two Type 1 diabetic adolescents (M-age = 15.97; SD = 3.45) were followed for one year. HbA1c was assessed at three time points, and a stress measure was obtained. Using a longitudinal growth curve modeling, a marginal overall negative linear trend was found in HbA(1c) (b = -0.23, p = 0.096). There was an interaction between time and PD (b = -0.33, p < 0.05), and a main effect of EB, RD, and ID on HbA(1c). Psychological stress domains predict metabolic control trajectories. Monitoring diabetes specific stress may be a useful tool to identify adolescents at risk for poor control, and interventions that reduce such stress might lead to better management of diabetes in adolescents.