A 22-year-old immunocompetent woman who presented with a 3-week history of fever, headache, and visual loss and was found to have subnormal visual acuity and bilateral optic disc swelling. Serum cytomegalovirus (CMV) IgM and IgG and polymerase chain reaction results were positive, indicating an acute CMV infection. No cause of immunocompromise was found. After treatment with intravenous ganciclovir, the papillitis and systemic CMV illness resolved with no residual deficit. This is the first reported case of primary CMV papillitis to be successfully treated with ganciclovir alone.