The purpose of the present investigation was to assess the antidiabetic property of Nyctanthes arbortristis leaves and flowers chloroform extract. In the present study antidiabetic properties of Nyctanthes arbortristis we investigated by hypoglycemic effect, potentiation action of exogenous insulin, oral glucose tolerance test and streptozotocin-induced diabetic rat model. The Nyctanthes arbortristis exerted hypoglycemic effect at relatively high dose 8 gm/kg of leaves and flowers chloroform extracts treated rats, significantly (P<0.05, P<0.01) lowered blood serum glucose levels, compared to 0 hrs.