Acupuncture has been widely used as a treatment for various conditions like headache and stroke, especially in Asian countries such as Korea and China. But few scientific investigations have been carried out. The aim of the present study is to investigate the effect of acupuncture on the production of inflammatory cytokines in patients with chronic headache (CH). Patients with CH were treated with acupuncture during the acute stage. Clinical signs of CH disappeared markedly after three months of treatment with acupuncture. Peripheral blood mononuclear cells obtained from a normal group and those from the patients with CH, before and after treatment with acupuncture, were cultured for 24 hours in the presence or absence of lipopolysaccharide (LPS). The amount of interleukin (IL)-1beta, IL-6 and tumor necrosis factor-alpha (TNF-alpha) in LPS culture supernatant was significantly increased in the patients with CH compared to the healthy control group (p < 0.05). But those cytokines came down toward the levels of the healthy group (p < 0.05) after treatment with acupuncture, although the levels still remained elevated. Plasma cytokine levels were analyzed to evaluate any change due to acupuncture treatment. There was little difference in the levels of IL-1 or IL-6 due to the treatment with acupuncture in the patients with CH, but significantly reduced plasma levels of TNF-alpha were observed. These data suggest that acupuncture treatment has an inhibitory effect on pro-inflammatory cytokine production in patients with CH.