Diabetes mellitus, a chronic metabolic disorder marked by hyperglycemia, affects millions worldwide. This study explores the antidiabetic potential of ethanolic extract of Pongamia pinnata leaves (EEPPL) using dexamethasone-induced diabetic rat models. EEPPL was prepared via Soxhlet extraction and tested in five groups (n=6 each): normal control (saline), positive control (dexamethasone 1 mg/kg), standard (metformin 40 mg/kg), low dose (EEPPL 250 mg/kg), and high dose (EEPPL 500 mg/kg). Treatments were administered for 10 days, with assessments on day 10 including body weight, fasting blood glucose (FBS), oral glucose tolerance test (OGTT), lipid profile, lipid peroxidation, and catalase levels. In vitro α-amylase and α-glucosidase assays were also conducted with acarbose as a reference. Results showed significant antidiabetic and antioxidant effects in dexamethasone-induced diabetic rats. The standard group had highly significant improvements in FBS and OGTT. The high-dose EEPPL group exhibited moderate to highly significant effects on FBS, OGTT, and lipid profile, with weight improvements and reductions in cholesterol levels. Antioxidant assessments revealed reduced lipid peroxidation and increased catalase activity in the high-dose group. The in vitro assays demonstrated dose-dependent inhibition of α-amylase and α-glucosidase, comparable to acarbose. In conclusion, the study suggests that EEPPL has notable antidiabetic and antioxidant properties, supporting its potential as a natural therapeutic for managing diabetes and oxidative stress.