Effects of Acanthopanax senticosus extract (AS) on blood sugar content and serum lipid profiles of streptozotocin-induced diabetic rats were investigated. Experimental groups were classified into four groups, that is, normal control (NC) group, diabetic mellitus (DM) group, AS-fed group and DMAS-fed group. The AS group showed lower feed efficiency than the NC group, but the efficiency of DMAS group was higher than DM group. DMAS group showed the decreased water intake and urine by $45.5\%$ and $23.7\%$ respectively, compared with DM group. Compared with DM group, DMAS group decreased blood sugar by $46.9\%$ and triglyceride by $17.8\%$, total cholesterol by $10.0\%$ and LDL cholesterol by $22.0\%$ in serum, but increased serum HDL cholesterol by $14.4\%$ The relative percentage of liver or kidney per body weight, and the serum ALT activity in DMAS group were lower than those of DM group. There were no significant differences in hepatic glutathione(GSH) contents and total xanthine oxidase(XOD) activities among experimental groups. The hepatic lipid peroxide(LPO) content in DMAS group decreased by $54.6\%$ compared with that in DM group. The XOD (O type) and the ratio of O type to total type of both STZ-treated groups (DM and DMAS) were higher than those of NC group, but less conversion of D to O type was observed in DMAS group than in DM group. There was no significant difference in GST activity between NC and AS, but STZ-treated groups showed lower glutathione S-transferase(GST) activity than NC. In conclusion, it seems that AS reduces blood sugar by inhibiting the activity of xanthine oxidase type O as an oxygen-free radical generating system which induces the tissue damage. Antidiabetic effect of AS may regulate diabetes-induced high lipid profiles in blood.