Background: Artemisiae annuae herba (AAH) has been traditionally used as a drug for the treatment of malaria, heat stroke, bacterial infection, and fever in East-Asia. Although AAH has been used for the treatment of inflammation-related symptoms, the underlying mechanism of antiinflammatory activity of AAH is still unknown. Objective: We investigated whether AAH have an inhibitory effect on the production of pro-inflammatory mediators in lipopolysaccharide-stimulated RAW 264.7 macrophage cells. Materials and Methods: The investigation was forced on the inhibitory effect of AAH on the production of tumor necrosis factor (TNF)-α, interleukin (IL)-6, nitric oxide (NO), and inducible NO synthase (iNOS) in macrophages. Furthermore, we examined the effect of AAH on the activation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) pathways. Results: We found that AAH suppresses NO production and TNF-α, IL-6, and iNOS gene expression. Moreover, AAH inhibited the nuclear translocation of p65 and IκBα degradation in NF-κB pathway and decreased the extracellular signal-regulated kinase, p38, c-Jun NH 2 -terminal kinase phosphorylation in MAPK signaling pathway. Conclusions: Consequently, these results indicate that AAH contains antiinflammatory activity and this effect is derived from the repression on the activation of NF-κB and MAPKs pathways. We first demonstrated that antiinflammatory effect of AAH and its underlying mechanism in macrophage cells.