Objective To examine the association of family organization with metabolic control in adolescents with type 1 diabetes through the mechanisms of family self-efficacy for diabetes and disease management. Method Data from the baseline assessment of a longitudinal RCT were used, wherein 257 adolescent–parent dyads (adolescents aged 11–14) each completed the family organization subscale of the Family Environment Scale, the self-efficacy for Diabetes Self-Management Scale, the Diabetes Behavior Rating Scale, and 2 24-hr diabetes interviews. Results Structural equation modeling showed greater family organization was associated indirectly with better disease management behaviors via greater family self-efficacy (β = .38, p < .001). Greater self-efficacy was indirectly associated with better metabolic control via better disease management both concurrently (β = –.37, p < .001) and prospectively (β = –.26, p < .001). The full model indicates more family organization is indirectly associated with better metabolic control concurrently and prospectively through greater self-efficacy and better disease management (β = –.13, p < .001). Conclusions Understanding the mechanisms by which family organization is associated with metabolic control provides insight into possible avenues of prevention/intervention for better diabetes management.