The Polizia di Stato (State Police or P.S.) is one of the national police forces of Italy. Alongside the Carabinieri, it is the main police force for providing police duties, primarily to cities and large towns, and with its child agencies it is also responsible for highway patrol (autostrade), railways (ferrovie), airports (aeroporti), customs (together with the Guardia di Finanza) as well as certain waterways, and assisting the local police forces.

It was a military force until 1981 when the Italian State Law 121 was passed. This converted the State Police to a civil force, which is in contrast to the other main police forces of Italy: the Arma dei Carabinieri, which is a military police (gendarmerie) force and the Guardia di Finanza, the Italian customs and border protection police that also falls in the military corps category.

The Polizia di Stato is the principal Italian police force for the maintenance of public security and as such it is run directly from the Dipartimento della Pubblica Sicurezza (Department of Public Security), and the keeping of public order (ordine pubblico). Interpol summarizes the primary focus of this force: "Its responsibilities include investigative and law enforcement duties, and the security of motorway, railway, and waterway networks".