Objective: To assess the presence of anxiety disorders and quality of life in patients with insulin-dependent type 2 diabetes. Methods: Case-control study of 996 patients with type 2 diabetes and 2,145 individuals without diabetes. The sole inclusion criterion for the case group was insulin-dependent type 2 diabetes. We compared the case and control groups for sociodemographic variables, laboratory and clinical data, and presence of anxiety disorders. Quality of life was evaluated using the WHOQOL-BREF instrument, and the prevalence of anxiety disorder was evaluated by the Mini International Neuropsychiatric Interview (MINI). Results: Patients with diabetes had a higher prevalence of generalized anxiety disorder, panic disorder, and obsessive-compulsive disorder. The presence of these disorders in combination with type 2 diabetes was associated with worse quality of life in the physical, social, psychological, and environmental domains. Conclusions: This study demonstrates the importance of diagnosing and treating anxiety disorders in patients with diabetes, so as to prevent more serious complications associated with these comorbidities.