Anemia is common among older adults, and a substantial proportion of anemia in the older population is of indeterminate cause. Low selenium levels have been associated with anemia in animals, but this relationship has not been well characterized in humans. The objective was to determine whether low serum selenium concentrations are associated with anemia among older women. We conducted a cross-sectional analysis of participants in the Women's Health and Aging Studies, a population-based sample of women living in the community in Baltimore, MD, USA. Of 632 women, aged 70-79 yr, 14.1% of women were anemic (hemoglobin <120 g/L). The prevalence of anemia among women in the lowest to highest quartile of serum selenium was 22.4%, 14.6%, 11.9% and 6.6%, respectively (p < 0.0001). An increase in loge selenium was associated with a reduced risk of anemia (odds ratio per 1 SD increase = 0.63, 95% confidence interval = 0.47-0.84), adjusting for age, education, chronic diseases, iron status, and serum interleukin-6. We conclude that low serum selenium is independently associated with anemia among older women living in the community.