ABSTRACT Bioflavonoid-containing diets have been reported to be beneficial in diabetes. In the current study, the effect of Biochanin A (BCA) on blood glucose, antioxidant enzyme activities and oxidative stress markers in diabetic rats were investigated. 30 male Wistar rats were divided into five groups. Two of them were selected as control; group1: control (receiving 0.5%DMSO), and group2: Control+BCA (receiving 10 mg/kg.bw BCA). Diabetes was induced in other rats with injection of (55 mg/kg.bw) streptozotocin; group3: diabetic control (receiving 0.5%DMSO), groups 4 and 5 were treated with 10 and 15 mg/kg.bw BCA respectively. After 6 weeks the following results were obtained. Fasting blood glucose (FBG), Triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C) and malondialdehyde (MDA) levels significantly increased and body weight, high density lipoprotein cholesterol (HDL-C), superoxide dismutase (SOD) and catalase (CAT) activity and total antioxidant status (TAS) significantly decreased in diabetic rats as compared to control rats. Oral administration of BCA in 10 and 15 mg/kg.bw, FBG, TG, TC, LDL-C, VLDL-C were decreased significantly in all treated rats. MDA was decreased in all treated rats but it was significant just in 15 mg/kg.bw BCA. HDL, CAT, SOD, and TAS were significantly increased in treated group with 15 mg/kg.bw. The obtained results indicated hypoglycemic and hypolipidemic effect of BCA. Also BCA reduced oxidative stress in diabetic rats.