We report a case of invasive sphenoid sinus aspergillosis with progressive internal carotid artery (ICA) stenosis and contralateral carotid occlusion that was successfully treated with percutaneous transluminal angioplasty and stenting (PTAS). A 70-year-old man presented with right-sided visual disturbance, ptosis, and left hemiparesis. Magnetic resonance imaging of the head revealed a space-occupying lesion within the sphenoid sinus with infiltration of the bilateral cavernous sinuses, right ICA occlusion, and multiple watershed cerebral infarcts involving the right cerebral hemisphere. The patient was diagnosed with invasive sinus aspergillosis based on transnasal biopsy findings. Despite intensive antifungal therapy using voriconazole, rapidly progressive aspergillosis led to a new stenotic lesion in the left ICA, which increased the risk of bilateral cerebral hypoperfusion. We performed successful PTAS to prevent critical ischemic events. Finally, aspergillosis was controlled with voriconazole treatment, and the patient was discharged. He showed a favorable outcome, with a patent left ICA observed at a 3-year follow-up. PTAS may be feasible in patients with ICA stenosis and invasive sinus aspergillosis.