Parkinsonian disorders such as Parkinson's disease (PD), multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and corticobasal degeneration (CBD), are a large group of common neurodegenerative diseases. The initial differential diagnosis can be extremely challenging with major implications for prognosis. The 42 amino acid fragment of amyloid-beta (Abeta42), neurofilament light chain (NFL), neurofilament heavy chain (pNFH), tau protein, glial fibrillary acidic protein (GFAP), neuron specific enolase (NSE), S-100B protein, and myelin basic protein (MBP) are brain related proteins (BRP) present in neurons and glia cells. They are released in the cerebrospinal fluid (CSF) after brain tissue damage caused by a variety of neurological diseases, including the parkinsonian disorders. A review of the literature shows that, carefully interpreted, the CSF levels of BRP can be of value in the differential diagnosis of parkinsonian disorders.