570-579Glabridin (component of Licorice), a major flavonoid of Glycyrrhiza glabra L. (Fabaceae), is commonly used in the treatment of cardiovascular and central nervous system diseases. Also, it has been associated with a wide range of biological properties such as antioxidant, anti-inflammatory, estrogenic and anti-osteoporotic. Here, we investigated the antidiabetic effects of oral treatment with glabridin on streptozotocin (STZ)-induced diabetic rats. Type 1 diabetes was induced in male albino rats by a single intraperitoneal injection of STZ (60 mg/kg body weight). Diabetes appeared after 1-3 days after STZ injection. The animals were randomly divided into6 groups (7 animals each) as follows; Group 1: Normal control group (negative control group); Group 2 & 3: glabridin-treated control groups (25&50 mg/kg body weight); Group 4:STZ diabetic group (positive control group); Group 5 & 6:glabridin treated diabetic groups(25&50 mg/kg body weight). In normal rats, no harmful effects were detected after orally administration of both doses of glabridin on all parameters measured.The anti-diabetic activity of glabridin (especially high dose) was mediated through significantly increased the body weight gain, enzymic/non-enzymic antioxidants and HDL-cholesterol, and significantly decreased relative organ weights, serum glucose, lipid profiles, lipid peroxidation (LPO), pro-inflammatory cytokine, liver and kidney functions. The present study indicated that the anti-inflammatory/anti-oxidant activity of glabridin (especially high dose) may have beneficial effects against complications shown in STZ diabetic rats