The anti-inflammatory effects of Sargassum fulvellum water extracts (SFWE) were investigated using lipopolysaccharide (LPS)-induced inflammatory response in this study. To examine the potential anti-inflammatory properties of SFWE, the NO, TNF-${alpha}$, IL-6, IL-$1{eta}$, and cell proliferation were measured. It was confirmed that the NO and TNF-${alpha}$ secretion were significantly suppressed when SFWE was added to LPS-stimulated RAW 264.7 cells. Moreover, the expression of IL-6 and IL-$1{eta}$ cytokines was suppressed by SFWE in a dose-dependent manner. Especially, IL-6 inhibition activities were over 50% at 1% of SFWE. The cytotoxicity of SFWE and the proliferation of macrophages was measured by MTT assay. As a result, there was no cytotoxicity in the macrophage proliferation treated with SFWE compared to the control. In conclusion, these results suggested that the SFWE may have significant effects on inflammatory factors and can be a potential anti-inflammatory therapeutic materials.