Interleukin-18(IL-18) is a new member of IL-1 cytokine family and known as IFN-γ-inducing factor previously. An increased secretion of IL-18 is generally a marker for many chronic inflammation and autoimmune disorders, implying its involvement in inflammatory responses. Here, it was showed that IL-18 stimulated the expression of CSF-1 in Jurkat T lymphocytes that might be a manifestation for IL-18 to play its biological functions in inflammatory pathogenesis. The signaling mechanism that contributes to IL-18-induced transcriptional activation of CSF-1 was investigated further. Combined data suggested a MyD88-NF-κB-CSF-1 signal pathway is involved in the up-regulated expression of CSF-1.