The aim of this study is to report a case of complete regression of diabetic macular edema after subcutaneous injection of exenatide in a patient with type 2 diabetes mellitus. This study is an interventional case report. Blood investigations, complete ophthalmic examinations and optical coherence tomography were performed. A 55-year-old female affected by poorly controlled type 2 diabetes mellitus presented with visual impairment due to macular edema in the right eye. The left eye showed mild edema without visual loss. Best-corrected visual acuity (BCVA) was 20/80 and 20/20, respectively. The patient was encouraged to improve metabolic control, and the antidiabetic therapy was modified combining exenatide 10 μg subcutaneously twice daily to her regimen of oral metformin. The patient did not receive any ocular treatment. A complete tomographic resolution of macular edema was observed after 1 month and BCVA improved to 20/63. These findings were confirmed for the entire 6-month follow-up duration. No ocular or non-ocular adverse events were recorded. This is the first reported case of complete regression of macular edema in a diabetic patient after subcutaneous injection of exenatide.