Abstract Objective: One of the common complications of acute infection of the paranasal sinus is cellulitis of the orbit. This is secondary to the spread of infection through the very thin bony wall between the ethmoid sinuses and the orbit, the roof of the orbit in frontal sinusitis, and the floor of the orbit in maxillary sinusitis. When the infection does not penetrate the periorbita, it dissects under the periosteum and forms subperiosteal abscess. Methods: We experienced 10 patients with subperiosteal abscess for 10 years from 1992 to 2002 that required surgical drainage. The age of the patients ranged from 4 to 76 years including five males and five females. Results: Successful and safe drainage of the abscess with endoscopic sinus surgery was obtained in four patients while six patients required external surgery. The selection of the surgical approach depended upon the localization of abscess in the orbit. Five of the seven patients with visual disturbance resulted in a complete recovery of vision after surgery. However, there was no improvement of visual acuity in the other two patients who had already shown severe damage of vision prior to treatment. Conclusion: Ocular symptoms such as exophthalmos, double vision, and ptosis subsided completely in all patients. It is suggested that prompt diagnosis and surgical drainage before severe loss of visual acuity rescue or recover the vision.