This is a case of acute idiopathic frosted branch angiitis in a 4-year-old African American girl with history of sickle cell trait. She developed bilateral, subacute vision loss attributed to acute idiopathic frosted branch angiitis and was treated with systemic corticosteroids with a good recovery of vision. Acute idiopathic frosted branch angiitis is a rare disease, usually with a good prognosis. This is, to our knowledge, the 10th reported case in the United States.