Objectives: Cinnamomi Ramulus (CR), the young twig of Cinnamomum loureirri nees, has been used for treating symptoms related to pain, rheumatic arthritis and inflammation in Korean herb medicine. This study was carried out to investigate the anti-inflammatory effect of CR in vivo and in vitro. Methods: Extracts of CR were prepared and the chemical components of the extracts were examined by gas chromatography-mass spectrometry (GC-MS). The extracts were administrated to the rat paw edema model induced by carrageenan to evaluate the anti-inflammatory effect of CR. The expressions of nitric oxide (NO), prostaglandin E2 (PGE2), inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 were also quantified in lipopolysaccharide(LPS)­induced RAW 264.7 macrophages to survey the effect of CR in vitro. The main components were cinnamaldehyde and coumarin. Results: We examined the anti-inflammatory activity of the $80\%$ ethanol extract of Cinnamomi Ramulus in vivo by using carrageenan-induced rat paw edema model. Maximum inhibition of $54.91\%$ was noted at the dose of l1000mg/kg after 2 hours of drug administration in carrageenan-induced rat paw edema and this showed a potent anti-inflammatory effect. Conclusions: The results showed that Cinnamomi Ramulus suppressed dose-dependently LPS-induced NO production in RAW 264.7 macrophages and also decreased iNOS protein expression. Cinnamomi Ramulus also showed a significant inhibitory effect in LPS-induced PGE2 production and COX-2 expression.