Type-2 diabetes mellitus (T2DM) is considered as a chronic metabolic disorder. Sesbania grandiflora (Family: Fabaceae; SG) is known for its antidiabetic activity however, there is no report for its fruit on such activity. Hence, the present study explores the anti-hyperglycemic potential of methanolic extract of SG (MSG) in a rat model of T2DM. T2DM was induced in male rats by a single injection of streptozotocin, 15 min after nicotinamide administration. MSG at both dose levels attenuated the plasma glucose level in rats subjected to glucose load similar to that of metformin. However, either dose of MSG did not alter the level of plasma glucose in normal rats. MSG (200 and 400 mg/kg) significantly attenuated the plasma glucose level in T2DM rats. Further, MSG at both dose levels attenuated T2DM-induced increase in the level of total cholesterol, triglyceride and low density lipoprotein, and decrease in the level of high density lipoprotein in the plasma of the rats. MSG (200 and 400 mg/kg) reduced the T2DM-induced increase in the level of lipid peroxidation and decrease in the activities of superoxide dismutase and catalase in both plasma and liver tissues. In addition, MSG at both dose levels reduced the T2DM-induced decrease in the level of expression of GLUT-4 in the liver. These results cumulatively suggest that the anti-hyperglycemic activity of MSG against T2DM condition could be due to the improvement in the aberrant lipid profile, oxidative stress and insulin sensitivity. Hence, MSG could be a potential candidate in the management of T2DM.