Objectives: To report a patient with ischemic orbital compartment syndrome as a complication of spinal surgery in the prone position. Design: Interventional case report. Methods: An 80-year-old man underwent a prolonged lumbar decompression laminectomy for spinal stenosis, under general anesthesia in the prone position. Several hours later, the patient complained of left periocular pain and reduced vision. Examination revealed significant facial edema, left proptosis, and a tight orbit, as well as no light perception and elevated intraocular pressure in the left eye, with complete internal and external ophthalmoplegia. Main Outcome Measures: Clinical course, imaging findings, management, and final outcome. Results: Magnetic resonance imaging confirmed the clinical diagnosis of a compartment syndrome with elevated intraorbital tension. A lateral canthotomy and cantholysis were performed, and high-dose IV steroids were started. The proptosis and facial swelling subsided gradually, but no improvement was noted in left visual acuity or left ocular movements. Conclusion: It is important to be familiar with this rare complication after prolonged surgery in the prone position. Although the prognosis seems to be poor, it is essential to monitor these patients perioperatively and to intervene surgically and medically once the diagnosis of orbital compartment syndrome is established.