We report a patient with pseudotumor with cystoid macular edema (CME). The initial finding in our case was only CME with a bilateral visual acuity decrease to 20/25. Approximately 3 months later, the visual acuity dropped to light perception in the right eye and 20/200 in the left eye. Computed tomography scan revealed a mass in the right orbital apex and band-shaped enhancement in the cavernous sinus and along the upper margin of the petrous bone. However, no mass was found intraoperatively, and a biopsy specimen of the bulging levator muscle showed polymorphonuclear leukocyte infiltration. The CME resolved postoperatively. The tumor also seemed to resolve; however, after 1 year, the tumor recurred and invaded the brain tissue. A temporal lobectomy revealed widespread inflammatory cell infiltration. To ensure early diagnosis, pseudotumor should be considered in patients with CME of which the cause is uncertain.