Simple bone cyst is a benign osteolytic lesion, found primarily in the mandible, occasionally in the maxilla, and rarely in the zygoma. A 17-year-old male patient with 6-month history of left facial mass presented with worsening proptosis and displacement of left eyeball associated with reduced OS vision. The lesion was painless to start with, but with time, he reported OS pain. There was no history of any trauma. CT scan and MRI of orbit performed revealed cystic bony lesion involving greater wing of sphenoid. He subsequently had excision of the left facial mass with exenteration of OS due to poor visual prognosis, followed by reconstruction with osteomyocutaneous flap from left scapular region. The histopathologic features were consistent with a diagnosis of simple bone cyst of zygomatic arch.