The aim of this study was to evaluate a possible role of soluble CD14 (sCD14) in multiple sclerosis (MS). We found that sCD14 serum levels measured by ELISA were higher in MS patients compared to neurological and healthy controls. Within the MS group sCD14 levels were increased in relapsing-remitting and secondary progressive MS compared to primary progressive MS. Furthermore, sCD14 concentrations were increased during stable disease. An increased expression of sCD14 was also detected after treatment with interferon-beta. In summary, we report evidence that serum sCD14 levels are increased in MS and correlate inversely with disease activity in relapsing MS patients.