Objective: CD14 is a receptor for endotoxin and binds components of Gram-positive and Gram-negative bacteria. CD14-bearing monocytes respond to stimulation with the increased synthesis and release of cytokines. The recently described –260 C→T promoter polymorphism of the CD14 gene has been found to be related to a risk of myocardial infarction. This study evaluated the role of this polymorphism in the expression of monocyte and soluble CD14. Moreover, the effect of the CD14 –260 genotypes for the ex vivo TNF-α response to endotoxin was analyzed in whole blood. Patients and participants: Ninety-five healthy blood donors were studied. Measurements and results: CD14 –260 genotyping was performed by means of a real-time PCR with fluorescence labeled hybridization probes. CD14 expression on human monocytes (mCD14) was assessed by fluorescence-activated cell sorting analysis with anti-CD14 monoclonal antibodies. Plasma levels of soluble CD14 (sCD14) were measured by ELISA. The TNF-α synthesis was determined by chemiluminescence in whole blood after endotoxin stimulation. There were no differences in mCD14 density, sCD14 levels, or the tumor necrosis factor-α concentrations between individuals with the three different CD14 –260 genotypes CC, CT, and TT. Conclusions: The CD14 –260 polymorphism does not affect the CD14 expression of unstimulated circulating monocytes or soluble CD14 plasma levels.