To improve the application of fucoidan in the biomedical field, we prepared glycol chitosan-fucoidan nanocomplexs (GC-Fu NC) through electrostatic interaction. The anti-inflammatory activities of GC-Fu NC were investigated in RAW 264.7 cells treated with lipopolysaccharide (LPS). Effects of GC-Fu NC on the production of proinflammatory factors (iNOS and COX-2) in LPS-stimulated RAW 264.7 cells were evaluated. GC-Fu NC were spherical with an average diameter of 406.0 ± 20.3 nm. In the cytotoxicity studies, GC-Fu NC did not show toxicity on RAW 264.7 at high concentration of 200 ppm. When LPS-stimulated RAW 264.7 cells were treated with GC-Fu NC, production of nitric oxide was inhibited in a concentration-dependent manner. In addition, induction of iNOS and COX-2 in the stimulated RAW264.7 cells was inhibited by treatment of GC-Fu NC. In conclusion, GC-Fu NC are expected to exhibit the effect of inhibiting the progression of inflammation. Furthermore, we expect that GC-Fu NC have great potential for application in food, cosmetics, and pharmaceutical industries.