The purpose of this study was to confirm the content of total polyphenol, antioxidative and immune activities of the extracts of Cedrela sinensis leaf. The content of total polyphenol of water extracts ranged from 46.5-59.6 mg/100 g, which was higher than other extracts using organic solvents such as EtOAc, $CH_2Cl_2$ and $C_6H_{14}$. The antioxidant activity of the water and organic solvents extracts showed 6-33% in terms of 2,2-diphenyl-picryl-hydrazyl (DPPH) scavenging activity. To analyze the immuno-stimulation activity of C. sinensis leaf extract, we investigated the effect of the extracts on NO synthesis which is important in host defense against bacterial infection. Hot water extracts significantly increased NO generation by RAW 264.7, macrophage cell line, while organic solvent extract has no significant effect on NO production. To further analyzed the anti-inflammatory effect of the extracts, we investigated the effects of the extracts on lipopolysaccharide(LPS)-induced NO generation. Organic solvent extracts of C. sinensis leaves showed strong inhibitory effect on NO production in LPS-stimulated RAW 264.7 cells. These results suggest that C. sinensis leaf extract may represent a useful immune stimulating agent and anti-inflammatory agent.