Invasive sphenoid sinus aspergillosis is a rare infection and usually affecting immunocompromised patients. We describe an invasive sphenoid sinus aspergillosis patient with immunocompetent who present progressive ocular dysfunctions. A 66-year-old woman with no history of immune dysfunction was referred to our hospital with orbital complications. Computed tomography (CT) scan and magnetic resonance imaging (MRI) showed a mass lesion extending from the left orbital apex to the sphenoid sinus. Inflammatory diseases were not suspected by laboratory findings, but a transnasal endoscopic biopsy revealed sphenoid sinus aspergillosis. After treatment of antifungal medication, this patient showed improvement and no sign of recurrence during the follow-up period. Diagnosis of invasive sphenoid sinus aspergillosis in an immunocompetent, healthy individual, was challenging. However, if patients have sinus wall deformities and orbital complications, early surgery is necessary to improve their prognosis.