Medicinal herbs and green manufacturing of silver nanoparticles (AgNPs) have been shown to be effective treatments for diabetes. Origanum majorana (OM) leaf extract is known for its potential medicinal benefits, including anti-diabetic activities. The study was aimed to assess efficiency of OML extract and nanoparticles in Streptozotocin (STZ) induced diabetic rats, as well as their histopathological effects on Liver tissue. 25 Rats were separated into 5groups : Group I: control non diabetic, Group II: injected with Streptozotocin (STZ) untreated diabetic group, Group III: diabetic rats treated with the glibenclamide, Group IV: diabetic rats were given OM leaf extract, Group V: diabetic rats were received OM leaf extract nanoparticles. Various parameters including blood glucose levels, insulin, lipid profile, liver functions test, antioxidant (MDA & GSH), and histopathological changes in liver were evaluated. Both OML extract and OMLNPs dramatically lowered blood glucose level when compared to the untreated diabetic group. Treatment with OMLNPs showed superior effects in improving insulin sensitivity, lipid profile, antioxidant and liver functions compared to the extract. Histopathological examination revealed that OM leaf extract and its nanoparticles mitigated STZ-induced damage in liver tissue, with a noticeable reduction in inflammatory infiltrates and cellular degeneration. OM leaf extract and nanoparticles show potential anti-diabetic and hepatoprotective effect, with enhanced efficacy possibly due to improved bioavailability.