Abstract The choroid plexus (CP), a component of the glymphatic system, is essential in homeostasis and producing cerebrospinal fluid. Role of CP in multiple system atrophy (MSA) remains unclear. This study aimed to investigate the implication of the CP in MSA. This retrospective cross-sectional study included 87 MSA patients who underwent the Unified MSA Rating Scale (UMSARS), brain MRI, and18F-fluorodeoxyglucose PET scan, along with 84 healthy controls (HCs).