The indications for endoscopic sinus surgery (ESS) have been widely expanding since its introduction into sinus surgery. ESS has become an ideal method to manage certain orbital diseases and has the advantages of excellent visualization with minimal cosmetic and functional morbidity. In the Department of Otolaryngology of Taichung Veterans General Hospital from 1988 to 2005, 3,136 patients received ESS. Among them, a total of 108 patients received ESS for orbital diseases. These orbital diseases included orbital complications secondary to bacterial rhinosinusitis, fungal rhinosinusitis, skull base osteomyelitis and mucoceles, subperiosteal hematoma, Graves' disease, traumatic optic neuropathy and orbital blowout fracture. Our results showed that ESS is effective in the management of some of these orbital diseases.