The anti‐diabetic and anti‐oxidant effects of 3 doses of an aqueous extract of raw ginger (Zingiber officinale) were studied in diabetic rats. Diabetes was induced by IP injection of streptozotocin (STZ) and a fasting blood sugar >300 mg/dl indicated diabetes. Diabetic rats were divided into 4 groups: control and 3 ginger‐treated groups. Ginger extract doses of 125, 250 and 500 mg/kg were administered daily for 8 weeks. Blood glucose and serum cholesterol, triglycerides, fructosamine, creatinine, uric acid, LDH and ALP were significantly elevated in diabetic rats, and significantly lowered by ginger dose‐dependently. Serum protein, albumin, total antioxidants and catalase (CAT) activity decreased significantly in diabetic rats, with 250 and 500 mg/kg ginger doses resulting in dose‐dependent increases. Liver and kidney malondialdehyde (MDA) and LDH, and liver ALP levels were significantly elevated in diabetic rats, and decreased by ginger dose‐dependently with the lowest dose having variable effects. In contrast, liver and kidney total antioxidants, protein and CAT activity were significantly decreased in diabetic rats, and were increased by the highest dose of ginger. Urine output, albumin, creatinine, and protein were significantly elevated in diabetic rats, and decreased by 250 and 500 mg/kg ginger doses. Thus, ginger exhibits a dose‐dependent effect in diabetic rats with the 500 mg/kg dose most potent in ameliorating oxidative stress and other indicators of diabetes in STZ‐induced diabetic rats.The study was supported by KFAS grant # 2007‐1302‐04.