CD14 is present in macrophage, monocyte, and granulocyte cells and their cell membranes, and its soluble fraction is present in blood and is thought to be produced in association with infections. It is called the soluble CD14 subtype, and its generic name is presepsin. Presepsin is a novel marker for the diagnosis of sepsis, and the results of previous study in which an ELISA kit was used showed a specific increase in sepsis in the early stage that also correlated well with severity. In the present study we developed a new rapid measurement method for whole blood that use a chemiluminescence enzyme immunoassay. We assessed the usefulness of presepsin values in sepsis.