This study examined whether depressive symptoms and/or diabetes distress mediate the association between relationship style and glycaemic control in women with diabetes. Seventy-five women with type 2 diabetes completed the Relationship Questionnaire. Participants endorsing “secure” or “preoccupied” adult attachment were combined into the interactive relationship style and “dismissing/avoidant” or “fearful” adult attachment were combined into the independent relationship style. Glycaemic control was a latent variable composed of A1c and 48-hr continuously measured glucose. Diabetes distress was assessed with the Problem Areas in Diabetes scale and depressive symptoms with the Center for Epidemiological Studies Depression scale. A parallel multiple mediation model with relationship style as the independent variable, glycaemic control as the dependent variable, and Problem Areas in Diabetes and Center for Epidemiological Studies Depression scale as mediators, tested indirect effects. Bias-corrected bootstrap with 10,000 replications was used to construct 95% confidence intervals. The indirect association of relationship style with glycaemic control through diabetes distress was significant (effect = −0.09, p = .036, 95CI = −0.19–0.01), but through depressive symptoms was not. A model testing the indirect association of relationship style with diabetes distress through glycaemic control was not significant. Results suggest that relationship style is associated with glycaemic control through diabetes distress in women with type 2 diabetes.