The hypolipidemic and hypoglycemic effects of two dietary dosages (0.1% and 0.5%) of water and 80% ethanol extracts from hot-air dried Orostachys japonicus A. Berger were evaluated in the serum and organ tissues of streptozotocin-induced diabetic rats. The STZ-induced diabetic groups supplemented with the O. japonicus extracts showed significantly higher body weight compared to a diabetic control group at the end of experiment. The extracts exhibited substantial hypoglycemic effects by significant reductions of fasting blood glucose levels at all time points tested compared to the initial stage before treatment of the extracts. Declines of serum and hepatic triglyceride levels were greater than declines of total cholesterol in the groups treated with the 0.5% O. japonicus extract (DBW2 and DBE2) when compared to the DBC group. Hepatic glycogen content was higher in the groups treated with O. japonicus extract, while lipid peroxide content was decreased in these treated groups compared to the DBC group. Hepatic antioxidant activity was significantly increased in the groups supplemented with the O. japonicus ethanol extract The hypolipidemic and hypoglycemic effects of the O. japonicus ethanol extract were significantly greater than the effects of the water extract. Based on this study, it seems that O. japonicus ethanol extract, due to its higher phenolic and flavonoid components than the water extract, may control blood glucose and alleviate hyperlipidemia in diabetes.