Objectives : This study was designed to test the effect of heating condition and Panax ginseng on body temperature, hematologicala changes, and immune response. Methods : The extract from Panax ginseng was made by the pharmacy department of Kyung Hee Oriental Medical Hospital. The animals were divided into four groups; control, room temperature Panax ginseng (G), $28^{circ}C$ heating, and $28^{circ}C$ heating Panax ginseng (heating G). Each group has 8 Sprague-Dawley rats. We measured body weight & temperature twice a week. After 2 weeks of experiment, serum lipid level, WBC, differential count, lymphocyte proliferation and immune cytokine concentration were measured. Results : 1. Simultaneous application of heating condition and Panax ginseng induced decreased body weight and increased body temperature. 2. Simultaneous application of heating condition and Panax ginseng induced decreased AST, ALT and BUN. 3. Simultaneous application of heating condition and Panax ginseng tended to decrease TNF-${alpha}$ concentration, while application of room temperature and Panax ginseng tended to increase TNF-${alpha}$ concentration. Conclusions : Simultaneous application of heating condition and Panax ginseng decreseas body weight, increases, body temperature and has a tendency to decrease TNF-${alpha}$ concentration.