Yookmijihwangtang has been widely used oriental herb prescriptions, which is healing some discuss that come from insufficiency of innate essence and deficiency of kidney Ki. The meaning of healing discusses tonification of insufficient innate essence and insufficient kidney Ki can be regarded as reinforcement of wholely power of keeping homeostasis, that is correlated with immuno-responsibility which protects subject from outer antigen to keep normal vital condition. This study was aimed to investigate correlative effects of Yookmijihwangtang water abstract on the RBC, WBC, blood CD4+ T helper cell count, blood testosterone, blood cAMP and blood cortisol. 40 Sprague-Dawley male rats were divided into 5 groups(Normal, Control, Sample I, Sample II, Sample III), 6 animals in every group. Normal group was not treated anything, control group was administrated normal saline in the same dosage of Sample I. 3 Sample groups were received some of Yookmijihwangtang water abstract at one time per 24 hours during 5 days in different dosage. Sample I(1/310pack/ml), Sample II(1/62pack/ml), Sample III(1/2.4pack/ml). After finishing treatment, all experimental subjects were killed for blood sample on RBC, WBC, blood CD4+ T helper cell count, spleen CD4+ T helper cell count, axillary lymph node CD4+ T helper cell count. blood cAMP, blood testosterone and blood cortisol. The results were as follows; RBC and WBC were increased in all sample groups. Blood CD4+ T helper cell count(CD4+ T cell count in the blood/whole lymphocyte count in the blood ${\times}100%$) was Normal $46.17{\pm}5.88$, Control $44.50{\pm}4.37$, Sample I $53.00{\pm}2.28$, Sample II $53.83{\pm}3.87$, Sample III $52.17{\pm}2.93$. By the 95% Duncan ANOVA all experimental groups(sample I, Sample II, Sample III) showed slight significant difference from Normal and Control. Blood cAMP(nmol/l) were Normal $1.12{\pm}0.17$, Control $1.16{\pm}0.32$, Sample I $0.46{\pm}0.07$, Sample II $0.44{\pm}0.04$, Sample III $0.54{\pm}0.04$. All experimental groups were singificantly different from both Normal and Control groups(p<0.05). Blood cortisol(nl/ml) were Normal $100.00{\pm}2.00$ Control $90.00{\pm}4.00$, Sample I $440.00{\pm}5.00$, Sample II $520.00{\pm}40.00$, Sample III $470.00{\pm}7.00$. Blood cortisol of all experimental groups were significantly increased(p<0.05). The results suggest that Yookmijihwangtang water abstract could be administrated to patients who have some diseases insufficient essence.