The aim of the present study is to investigate the antioxidant activities of the aqueous extract of seeds of two varieties, namely a country and hybrid variety of Momordica charantia (MCSEt1 and MCSEt2) respectively in streptozotocin induced diabetic rats. Oral administration of both the seed extracts at a concentration of 150 mg/kg b.w for 30 days showed a significant decrease in fasting blood glucose, hepatic and renal thiobarbituric acid reactive substances and hydroperoxides. The treatment also resulted in a significant increase in reduced glutathione, superoxide dismutase, catalase, glutathione peroxidase and glutathione-s-transferase in the liver and kidney of diabetic rats. The results clearly suggest that seeds of Momordica charantia treated group may effectively normalize the impaired antioxidant status in streptozotocin induced-diabetes than the glibenclamide treated groups. The extract exerted rapid protective effects against lipid peroxidation by scavenging of free radicals there by reducing the risk of diabetic complications. The effect was more pronounced in MCSEt1 compared to MCSEt2.