Diabetes mellitus (DM) is a chronic metabolic disease caused by abnormal insulin secretion characterized by increased blood glucose levels. Long-term use of drugs also causes side effects. Alternative therapies are needed with potential and mechanisms of action that are close to the body's physiological processes in controlling blood glucose so as to help reduce the development and complications of diabetes mellitus, and can be obtained at an affordable price. This study aims to test the effectiveness of green tea leaf extract in lowering blood sugar levels in male mice induced with dexamethasone. The type of research used is an experimental method with a Pretest-Posttest Control Group Design. This study tested the hypoglycemic effect of ethanol extract of green tea leaves on mice induced with dexamethasone 2.5 mg/kgBW of mice orally. The study began with the collection of green tea leaf samples, the manufacture of simplicia, and testing the hypoglycemic effect for 15 days of research. Ethanol extract of green tea leaves has a hypoglycemic effect on white mice induced by dexamethasone. EEDTH dose of 1.25 g/KgBW in rats showed better hypoglycemic potential compared to glibenclamide in a rat model induced by dexamethasone.