Abstract Objectives To investigate prevalence and clinical factors associated with diabetes among middle-aged women. Methods In this cross-sectional population-based study, clinical and laboratory examinations were collected from 298 women. Participants wore a digital pedometer for 7 days to assess habitual physical activity. Abdominal computed tomography scans were performed to measure total fat area and visceral fat area. Results Mean age was 57.1 years (SD, 5.4 y); 78.7% of women were postmenopausal. The prevalence of diabetes was 17.1%. Women with diabetes were older (P = 0.02); worked fewer hours per week in the past month (P = 0.04); had an earlier age at menarche (P = 0.03); were more frequently inactive (P = 0.01); had higher body mass index (P = 0.01), higher waist circumference (P < 0.01), higher visceral (P < 0.01), and higher total fat (P < 0.01) but not subcutaneous fat (P = 0.14); and had higher systolic blood pressure (BP) (P < 0.01). There was a prevalence of 19.5% of current smoking, 32.5% of alcohol use, and 16.1% of current hormone therapy use, prevalence similar among the groups of women. There was a higher prevalence of metabolic syndrome (P < 0.01) and statin use (P < 0.01) in women with diabetes. A higher prevalence ratio of diabetes was associated with physical inactivity (prevalence ratio, 2.137; 95% CI, 1.056-4.325; P < 0.03). The odds of having diabetes increased by 12% for each year of earlier menarche and by 1.4% for each millimeter of mercury increase in systolic BP. Conclusion The prevalence of diabetes was 17.1%. Age, physical inactivity, early age at menarche, and systolic BP were independently associated with higher prevalence of diabetes in this unselected population of middle-aged women.