Diabetes is a chronic disease caused by insufficient insulin production or ineffective use of insulin. Insulin regulates blood sugar levels. Approximately 463 million adults (20–79 years) have diabetes, expected to rise to 700 million by 2045. Celtis philippensis, from the Ulmaceae family, is widely distributed in India at altitudes of 1400 m. Phytochemical screening of aqueous, methanol, ethanol, ethyl acetate, chloroform, and hexane extracts showed alkaloids, sterols, carbohydrates, glucosides, terpenoids, saponins, tannins, gums, mucilage, and flavonoids. Acute oral toxicity tests in mice with 2000 mg/kg showed no toxicity or mortality over 14 days. Glucose tolerance and dexamethasone-induced tests confirmed anti-diabetic activity, with increased HDL levels in treated groups compared to diabetic controls. © 2020 Elsevier B.V., All rights reserved.