A 48-year–old woman presented to the emergency department with a 2- week history of right headache and orbital pain, with worsening symptoms of right upper eye lid swelling and erythema during the last 4-days. She denied any visual disturbance and weakness. She was initially managed by ophthalmologist with intravenous antibiotics (amoxicillin-clavulanate, clindamycin) and mannitol, but symptoms had not improved. Nasal endoscopic examination showed mucopurulent discharge from right middle meatus. The orbital computed tomography revealed a superiorly-based subperiosteal orbital abscess and significant paranasal sinusitis coexisting with suspicious fungal sinusitis. The abscess pocket was accurately pointed out through image-guided endoscopic view with the ostium seeker tracker. After removal of affected ethmoidal cells, bony dehiscence of lamina papyracea was identified. We performed the complete drainage of subperiosteal orbital abscess with normal saline irrigation and eyeball massage. One week postoperatively, the patient was relieved from the orbital pain and swelling without any sequelae.