Background: Diabetes mellitus is one of the most prevalent conditions in the world and it is one of the top most cause of death in the United States of America, India, Europe and Asia. In India, the prevalence of diabetes mellitus particularly type 2 is predominant when compared to the western population. Though anti-diabetic drugs play a major role in managing, treating and preventing diabetes mellitus, the adverse effects are known. Objective: The objective of the present study is to evaluate the Bauhinia purpurea against streptozotocin and high fat diet induced diabetes in rats. Methods: The animals were grouped into six groups (n=6) in each group. Normal control rats were administered normal saline (0.5 ml/kg orally by oral gavages) daily. Diabetic rats induced with a single dose of streptozotocin (40 mg/kg b. w., i. p.). Rats were administered with vanaspati + coconut oil (3:2) (0.5ml/kg. bwt) orally daily for 28 days to induce a high fat diet (HFD) and then diabetes induction was done. Diabetic rats were administered with HFD and co-treated with ethanolic extract of Bahunia purpurea (EEBP) (250 mg/kg b. w.) orally. Diabetic rats were administered with HFD and co-treated with ethanolic extract of Bahunia purpurea (500 mg/kg b. w.) orally daily. Diabetic rats were administered with HFD and co-treated with metformin (250 mg/kg b. w.) orally daily.