OBJECTIVE The authors describe clinical characteristics of acute exudative polymorphous vitelliform maculopathy syndrome, also termed polymorphous maculopathy syndrome (PMS), an unusual tapetoretinal disorder first reported by Gass. METHODS Detailed ophthalmoscopy, fluorescein angiography, electrophysiology, and optical coherence tomography (OCT) were performed on a patient with PMS. RESULTS Numerous small, yellowish lesions arranged in a honeycombed pattern at the level of the retinal pigment epithelium (RPE) around the disk and the macula, a shallow macular detachment (documented by OCT), and a perifoveolar yellow ring appeared in both eyes. Initial fluorescein angiography revealed mild early hyperfluorescence and late staining of the perifoveolar rings and the multifocal yellow lesions. Gradually, subretinal yellowish deposits gravitated as a meniscus below the macula with subsequent further changes. Electrophysiology showed reduced amplitudes of the electroretinogram and electrooculogram and abnormal dark adaptometry. A rhegmatogenous retinal detachment in the left eye was successfully repaired, with a visual acuity of 20/30. Antecedent upper respiratory infection and headaches and positive serology for the coxsackie virus suggest the possibility of a virus-induced disorder. Genetic studies of this patient showed normal DNA sequences for the bestrophin and peripherin/RDS genes. CONCLUSIONS This is the first report of PMS with the following characteristics: occurrence in a woman, development of a rhegmatogenous retinal detachment, and electroretinogram, visual-evoked response, color vision, and OCT findings. PMS has features similar to but also different from those of Harada disease and Best disease. Further studies are necessary to determine its relationship to other acquired conditions, such as virus-induced disorders, and genetic defects unrelated to abnormalities of the bestrophin and peripherin/RDS genes.