Blood count parameters are associated with the metabolic syndrome (MS). However, few studies have evaluated the precision of blood count components to identify MS in older adults. We evaluated the accuracy of blood count components as a screening method and a marker of MS in older adults.A cross-sectional study with 203 older adults of both sexes was conducted. The following variables were used: MS as defined by harmonized criteria, hemoglobin, hematocrit, leukocytes and platelets. Area under the receiver operating characteristic (ROC) curve, sensitivity (sens), specificity (spec) and logistic regression were adjusted for age and sex. Leukocyte count showed the highest Youden's index value for MS screening, with an optimal cut-off point of 7.514103/mm3 (sens: 66.7%; spec: 72.0%) for men and 5.626103/mm3 (sens: 73.1%; spec: 42.4%) for women. Older adults with leukocyte count higher than these cut-off points presented a 2.4 times greater chance of developing MS.Leukocyte count can be used as a screening indicator to identify individuals with a higher risk of developing MS. Older adults with high leukocyte count and no associated chronic diseases should receive attention, as they are individuals with a potential risk for MS.