In India, Tectona grandis is traditionally used in the treatment of diabetes mellitus and lipiddisorder. In the present study, the antihyperglycemic and lipid lowering effect of ethanolic extractof bark of Tectona grandis (TG) was evaluated using alloxan induced diabetes in rats. Alloxan wasgiven at the dose of 140 mg/kg, i.p. After induction of diabetes, TG was administered for 42 daysp. o. and simultaneously different biochemical parameters like plasma glucose, liver glycogencontent, serum triglyceride, cholesterol, LDL-cholesterol and HDL-cholesterol were estimated.Diabetic control showed significant increase (P < 0.01) in plasma glucose, serum triglyceride,cholesterol, LDL-cholesterol and significant decrease (P < 0.01) in serum HDL-cholesterol andliver glycogen content. Treatment with TG showed significant reduction (P < 0.01) in plasmaglucose when compared with diabetic control. The elevated levels of serum triglyceride andcholesterol levels were significantly reduced (P < 0.01) by TG. TG treatment for 42 days showedsignificant decrease in serum LDL-cholesterol (P < 0.01) and significant increase in serum HDL-cholesterol level (P < 0.01). Moreover, diabetic control there was significant decrease in liverglycogen content which was significantly increased (P < 0.05) by treatment with TG. Hence, fromthe result obtained in the present study it can be concluded that Tectona grandis has the potentialto treat diabetes condition and associated lipid disorder.