Aim: To examine the association between antidepressant medication use and the risk of type 2 diabetes. Methods: Data were obtained from the E3N study (Étude Épidémiologique de Femmes de la Mutuelle Générale de l'Éducation Nationale), a French cohort study initiated in 1990, with questionnaire-based follow-up every 2 or 3 years. Exposure to antidepressants was obtained from drug reimbursement files available from 2004 onwards, and individually matched with questionnaire data. Cases of type 2 diabetes were identified from drug reimbursements. Cox proportional-hazard regression models were used, with drug exposure considered as a time-varying parameter. Results: Of the 63 999 women who were free of drug-treated type 2 diabetes at baseline in 2005, 1124 developed type 2 diabetes over the 6-year follow-up. Current use of antidepressants was associated with an increased risk of type 2 diabetes [hazard ratio 1.34 (95% CI 1.12, 1.61)] compared to non-users. When the different types of antidepressants were considered, women who currently used selective serotonin reuptake inhibitors, imipramine-type, 'other' or 'mixed' antidepressants had a 1.25-fold (95% CI 0.99, 1.57), 1.66-fold (95% CI 1.12, 2.46), 1.35-fold (95% CI 1.00, 1.84) and 1.82-fold (95% CI 0.85, 3.86) increase in risk of type 2 diabetes compared to non-users, respectively. Conclusion: Our study suggests a positive association between antidepressant use and the risk of type 2 diabetes among women. If this association is confirmed, screening and surveillance of glucose levels should be considered in the context of antidepressant therapy. Further studies assessing the underlying mechanisms of this association are needed. (ClinicalTrials.gov identifier: NCT03285230).