To report a case of macular edema after the use of the oral hypoglycemic agent rosiglitazone.

A 43-year-old man, who had diabetic mellitus and was on oral rosiglitazone therapy, complained of a visual disturbance in his left eye. After fundus examination and optical coherence tomography, macular edema was observed, therefore rosiglitazone therapy was discontinued.

After 2 weeks, his visual acuity improved, and macular edema decreased in the left eye on optical coherence tomography.

Rosiglitazone use should be considered as one of the potential causes of macular edema.