The purpose of this study was to compare abdominal aortic aneurysm (AAA) associations in men and women.Veterans aged 50 to 79 years without a previous history of AAA underwent ultrasound screening for AAA after completing a questionnaire on demographic information and potential risk factors.A total of 122,272 men and 3450 women were successfully screened. An AAA of 3.0 cm or greater in diameter was found in 4.3% of men and 1.0% of women (P <.001). Contrary to a previous report, we did not find suprarenal aortic enlargement accompanying AAA to be more common in women. The principal associations that we have previously reported for AAA in this cohort (age, smoking, family history of AAA, and a negative association with diabetes) were all similar in women compared with men. In age- and smoking-adjusted models, the interaction terms indicated that black race and cancer were more strongly associated with AAA in women than men (P <.05). Height and cerebral vascular disease were also more strongly associated with AAA in women than in men, but these interaction terms did not reach statistical significance (P <.10). Although the other differences were unexpected and require confirmation, the trend toward a stronger association of cerebral vascular disease with AAA in women is consistent with two previous reports.Despite the much lower prevalence of AAA in women, the most important associations with AAA are similar to those seen in men. Our data provide some support for a previous finding that cerebrovascular disease may be more closely associated with AAA in women than in men.