Mangifera indica (mango), a member of the Anacardiaceae family, is renowned for its diverse pharmacological properties, encompassing antidiabetic, antioxidant, antiviral, cardiotonic, hypotensive, and anti-inflammatory effects. The present study delves the insulin-releasing and glucose-lowering potential of the ethanolic extract of Mangifera indica (EEMI) leaves in streptozotocin (STZ)-induced type 2 diabetic rats, concurrently investigating its phytoconstituents. EEMI's effects on insulin secretion were measured using BRIN BD11 β-cells and isolated mouse islets. It’s enzymatic inhibitory properties on carbohydrate digestion, glucose absorption, and free radicals were investigated using starch digestion, glucose diffusion and DPPH assay methods. In-vivo parameters including lipid profile and liver glycogen content were assessed on streptozotocin-induced type 2 diabetic rats. EEMI exhibited a dose-dependent increase in insulin secretion from clonal pancreatic BRIN BD11 β-cells and isolated mouse islets. EEMI inhibited starch digestion, glucose diffusion over time and DPPH activity in vitro. In acute in vivo studies, EEMI improved food intake, oral glucose tolerance. Moreover, following 28 days of treatment with EEMI, a remarkable amelioration in body weight, fasting blood glucose, plasma insulin, liver glycogen content, total cholesterol, triglyceride, LDL, VLDL and HDL levels were observed. Further phytochemical analysis with EEMI identified the presence of alkaloids, tannins, saponins, steroids, glycosides, flavonoids, and reducing sugar. The synergistic effects of EEMI, potentially attributable to naturally occurring phytoconstituents, hold promise for the development of enriched antidiabetic therapies, offering a promising avenue for the management of type 2 diabetes.