Progressive Supranuclear Palsy (PSP) is a progressive neurodegenerative syndrome characterized by supranuclear palsy, postural instability, and mild dementia. Neuropathologically, PSP is a four-repeat tauopathy, defined by the accumulation of neurofibrillary tangles and tufted astrocytes. Etiology remains elusive, but genetic background has a key-role in the disease pathogenesis. Recent studies have reported high familial aggregation in PSP patients, and it has been widely demonstrated that Microtuble Associated Protein Tau (MAPT) gene mutations are causative of monogenic autosomal dominant PSP. In sporadic cases, genetic advances have further confirmed the role of MAPT in increasing disease risk, and the H1 MAPT haplotype has been consistently associated with PSP, while the H2 haplotype seems protective. Conversely, no major environmental risk factors have been reported so far. A proper evaluation of known susceptibility factors related to PSP pathogenesis may help in defining neuroprotective therapeutic approaches.