ABSTRACTObjective: The objective of the study was to evaluate the antihyperglycemic activity and in vivo antioxidant effect of Artocarpus hirsutus seeds in bothnormal and diabetic rats.Methods: Male Wistar rats weighing about 180-250 g were divided into six groups, of six rats each. Diabetes was induced by giving streptozotocin(30-50 mg/kg) intraperitoneally. Rats, which showed blood glucose levels ≥250 mg/dl, were selected for the study. Metformin (50 mg/kg) was used as a standard oral hypoglycemic agent. Oral glucose tolerance test was performed in all groups of rats. In the estimation of in vivo antioxidant activity,the levels of liver enzymes superoxide dismutase (SOD), lipid peroxidation, and CAT (catalase) were measured using standard methods.Results: The ethyl acetate seed extract of A. hirsutus at different doses was selected and administered orally. The blood glucose levels were estimatedby the glucose oxidase method, and insulin levels were measured by chemiluminescence assay method. Antihyperglycemic activity of the test drugin diabetic rats showed a significant reduction in blood glucose levels (p<0.001) at 2, 4, 6, and 8 hrs, respectively, as compared to diabetic groups.The antioxidant enzymes SOD and CAT levels were significantly raised, whereas malondialdehyde-thiobarbituric acid residue substances levels havedecreased (p<0.001).Conclusion: The results suggested that A. hirsutus seed extract showed a potential antidiabetic activity and antioxidant effect justifying the use of thedrug for the treatment of diabetes mellitus and its associated oxidative damage.Keywords: Antidiabetic, Antioxidant, Artocarpus hirsutus, Streptozotocin