The anti-inflammatory activity of water extract of Mahaengeuigam-Tang(MHEGTWE) was examined using the carrageenin and acetic acid induced edema, croton oil induced granuloma pouch, and adjuvant arthritis in rats. In addition, the acute toxicity, analgesic and antipyretic effects of MHEGTWE were investigated by the general experimental methods. In acute toxicity test in mice, MHEGTWE showed 10% mortality at 2400 mg/kg(p.o), but it did not showed at 1200 mg/kg(i.p). It was also showed significant analgesic action on the writhing syndrome induced by 0.7% acetic acid at 600 mg/kg(p.o) and its antipyretic activity was observed in the typhoid vaccine induced fevered rats at 300 mg/kg(p.o). By the oral administration of the MHEGTWE, the significant anti-inflammatory activity was observed on 1% carrageenin induced edema, and it significantly inhibited the granuloma and exudate formation in rats. In the adjuvant arthritis experiment, the MHEGTWE decreased the hind paw edema in rats for 19 days. The results suggest that MHEGTWE has analgesic, anti-inflammatory and antipyretic action.