This study was designed to investigate the anti-inflammatory effect of oyster shell extract on the production of pro-inflammatory factors [NO, reactive oxygen species (ROS), nuclear factor-kappa B (NF-${kappa}B$), inducible nitric oxide synthase (iNOS) and cycloxygenase-2 (COX-2)] and pro-inflammatory cytokines [Interleukin-$1{eta}$ (IL-$1{eta}$), Interleukin-6 (IL-6) and TNF-${alpha}$] in the lipopolysaccharide (LPS)-stimulated Raw 264.7 cells. Cell viability, as measured by the MTT assay, showed that oyster shell extract had no significant cytotoxicity in Raw 264.7 cells. The treatment with oyster shell extract decreased the generation of intracellular reactive oxygen species dose dependently and increased antioxidant enzyme activities, such as SOD, catalase, GSH-px in LPS-stimulated macrophage cells. Oyster shell extract significantly suppressed the production of NO and also decreased the expressions of iNOS, COX-2 and NF-${kappa}B$. Additionally, oyster shell extract significantly inhibited the production of IL-$1{eta}$, IL-6, and TNF-${alpha}$ in LPS-stimulated Raw 264.7 cells. Thus, these results showed that the oyster shell extract had an anti-inflammatory effect on LPS-stimulated Raw 264.7 cells.