Frosted branch angiitis is a rare disorder. It is characterized by acute bilateral or unilateral visual loss with dramatic fundus abnormalities. These include marked sheathing of the retinal veins resembling frosted tree branches, retinal edema, late perivenous leakage on fluorescein angiography, and relative sparing of the optic nerve and retinal arterioles. In this report, we present a case of unilateral acute frosted retinal periflebitis in a 22 - year - old woman. The patient responded to topical and oral corticosteroid therapy 10 days after presentation.