Peripheral arterial disease (PAD) is an inflammatory process. The association between white blood cell (WBC) count and PAD in those with and without traditional risk factors is not clear. We examined data from the National Health and Nutrition Examination Survey (NHANES) 1999 to 2004. A total of 5260 participants were included. The result showed that the prevalence of PAD rose from 2.8% +/- 0.5% in the lowest quartile of plasma WBC count to 8.0% +/- 1.2% in the highest quartile. In subgroup analysis, the graded association between WBC count and PAD was significant in patients without hypertension, diabetes, smoking, chronic kidney disease (CKD), and in patients with or without hypercholesterolemia but not significant in patients with hypertension, smoking, diabetes, or CKD. In those without hypertension, diabetes, smoking, or CKD, the cutoff value for WBC count was 6.75 x 10(9)/L. We concluded that the positive association between WBC count and PAD can be demonstrated in this national survey.