Antidiabetic effects of Vigna unguiculata Linn. Walp (barbati) seed oil was investigated in albino rats by administration of single dose of alloxan monohydrate [110 mg/kg body weight (b.wt)]. The seed oil of barbati at doses of 100 and 200 mg/kg.b.wt was administered as single dose per day to diabetes-induced rats for a period of 21 days. The effect of oil on blood glucose level was measured in the diabetic rats. Serum lipid profile [total cholesterol (TC), triglycerides (TGs), low density (LDL) and high density lipoprotein (HDL)] and enzymes such as alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were also determined. The activities were also compared to that produced by a standard antidiabetic agent, glipizide. Levels of blood glucose, TC, TGs, LDL, ALT, AST and ALP decreased and HDL increased in alloxan induced diabetic rats after treatment with 200 mg/kg.b.wt barbati seed oil for 21 days. The present study reported that seed oil of barbati may be very useful for the improvement of the complications of diabetes.