A 70-year-old man, who was recently diagnosed with sclerosing mesenteritis following an abdominal biopsy, presented with an acute onset of left upper eyelid swelling, moderate ptosis, mild chemosis and restriction of movements. A computed tomography scan showed an enlarged lateral rectus muscle with surrounding soft tissue changes. A diagnosis of orbital inflammation manifesting as myositis was made and the patient was commenced on high-dose prednisolone, which showed a rapid response. It is believed that this may be a new association similar to that previously reported with retroperitoneal fibrosis and orbital inflammation.