A 57 year-old man developed broad-based unsteady gait and memory loss over a period of one year. On admission, bradykinesia and impairment of postural reflex were evident. Mini-mental state examination scored 27/ 30. Urinary control was normal. MRI revealed symmetric dilatation of lateral and 3rd ventricles, but the 4th ventricle appeared normal. Partial obstruction of the aqueduct with a membranous structure was disclosed by fast imaging employing steady state acquisition (FIESTA), and the diagnosis of late-onset aqueductal membranous occlusion (LAMO) was made. The symptoms were ameliorated shortly after endoscopic aqueductoplasty (EAP) and endoscopic third ventriculostomy (ETV). Membranous occlusion of the aqueduct can be detected by FIESTA and it can be cured by neuro-endoscopic measures.