Purpose : The study for changes in components and acitvities of Artemisiae Herba at various processing temperature is generally regarded as a foundation in setting the optimum heat-processing temperature and for getting the maximum activities for medical usage of this herb. Methods: Therefore some experiments were performed either in vitro or in vivo and various changes were observed - the changes in the weitht of Artemisiae Herba, the changes in the relative amount of three kinds of extracts from Artemisiae Herba ( diluted ethanol extract, water extract, ether extract ), the TLC pattern of essential oil at various processing temperature, the existance of inhibitory effects both on ${eta}$-Glucuronidase activities, and on heat-induced hemolysis, the effects on increased vascular permeability. The valid results derived from the experiments are as follows. Results: 1. The weight of Artemisiae Herba prominently decreased at 240^{circ}C$. 2. The contents of diluted ether extract were maximum in the unprocessing condition. Those of water extract were maximum at 180^{circ}C$ and at 210^{circ}C$. and the changes of diluted ethanol extract at 150^{circ}C$. 3. The TLC pattern of essential oil in Artemisiae Herba at various processing temperature showed that a component began to increase at Rf 0.56 and another component began to decrease at Rf 0.86. 4. The contents of Eupatilin in Artemisiae Herba at various processing temperature continued to decreased in proportion to the temperature rise, the extent of which was prominent at 210^{circ}C$, and was unnoticeable at 270^{circ}C$. 5. Inhibitory effects on ${eta}$-Glucuronidase activities, trypsin activities and heat-induced hemolysis increased in proportion to the density of Artemisiae Herba. Inhibitory effects on ${eta}$-Glucuronidase activities and trypsin activities were relatively high at 180^{circ}C$ while on the writhing syndrome and inhibitory effects on increased vascular permeability induced by acetic acid were maximum at 240^{circ}C$. those on heat-induced hemolysis were relatively high at 240^{circ}C$. 6. In vivo, both analgesic effects Conclusions: To maximize of the effectiveness of Artemmisiae Herba, the ideal heating temperature is in the range of 180^{circ}C{sim}240^{circ}C$.