The anti-inflammatory effect of the methanolic extracts of some medicinal plants was investigated on the hydrolysis of N-benzoylarginine-p-nitroanilide by trypsin in vitro, the writhing syndrome induced by acetic acid in mice, and the carrageenin-induced paw edema in rats. Among tested medicinal plants, the methanoilc extract of Angelica keiskei, Rosa rugosa and Cudrania tricuspidata showed significant inhibitory effect. And we also found that adenosine, isolated from A. keiskei was identified as one active components.