To examine the relationship between systemic immune status and carotid atherosclerosis in elderly men, differential leukocyte counts and lymphocyte subpopulations were measured in 557 apparently healthy Japanese men aged 60–75 years. Each individual also underwent high-resolution ultrasonography for measurement of intima-media thickness (IMT) of the common carotid arteries. The increased numbers of circulating lymphocyte subpopulations, including memory T cells (CD4+CD45RO+T cells) and late-phase activated B cells (CD19+CD80+B cells) correlated significantly and positively with the mean IMT of the common carotid artery after adjustment for age, smoking, and other cardiovascular risk factors. The positive associations of CD19+CD80+B and CD4+CD45RO+ T cell counts with mean IMT were more evident among nonsmokers, hypertensives, and men with lower HDL-cholesterol levels. The present epidemiological study provided the evidence that alterations in lymphocyte subpopulations, in particular memory T cells and late-phase activated B cells concur with carotid atherosclersosis among free-living elderly men.