Patients with type II diabetes mellitus were assessed for symptoms of depression using the Zung Self-Rated Depression Scale (Zung SDS) and the Beck Depression Inventory (BDI). The patients were classified according to the presence or absence of diabetic complications, and they were compared with a group of demographically matched, nonmedically ill control subjects. The patients with diabetic complications scored significantly higher on the depression inventories than did the patients without complications and the control subjects. Factor analysis of BDI responses revealed that cognitive symptoms of depression were prominent in the diabetic patients with complications. In this group, 74% of patients scored within the range of clinical depression on the BDI; 35% scored within the range of severe depression. Symptoms of sexual dysfunction were significantly correlated with symptoms of depression in diabetic women but not in diabetic men. The findings are discussed within the context of other research in the behavioral aspects of diabetes mellitus.