Choroid plexus cysts (CPCs) are a type of neuroepithelial cysts, benign lesions located more frequently in the supratentorial compartment. Symptomatic CPCs in the posterior fossa are extremely rare and can be associated with obstructive hydrocephalus. A previously healthy elderly woman suffered intermittent attacks of headache and vomiting associated with gait instability. Magnetic resonance imaging documented a large cystic lesion occupying all the fourth ventricle. An endoscope-assisted fenestration of the lesion through a telovelar approach determined only temporary improvement, hence a second surgery with gross total resection of the cyst was performed, with successful long-term clinical and radiologic resolution. Histology revealed CPC. Fourth ventricle symptomatic CPCs are extremely rare lesions, especially in the elderly. Their presence must be carefully evaluated as a possible rare cause of intermittent obstructive hydrocephalus. Even though cyst fenestration with restoration of the cerebrospinal fluid pathway represents the best treatment in the majority of cases, a more aggressive resection is sometimes necessary.