The hypoglycemic activity of aerial parts of Phyllanthus longiflorus (PHL) was studied against alloxan induced hyperglycemic rats. The activity was assessed by various parameters such as blood glucose level and serum level of triglyceride (TG), total cholesterol, low density lipoprotein (LDL), very low density lipoprotein (VLDL) and high density lipoprotein. A significant decrease in blood glucose, TC, TG, LDL, VLDL and a significant increase in HDL was observed after drug/extract treatment. The extract exhibited free radical scavenging activity on DPPH and superoxide anion free radical and also shown reducing property. From the results of the present study, it was concluded that PHL possessed potent hypoglycemic activity, probably by its antioxidant activity.