Provost marshal is a title given to a person in charge of a group of Military Police (MP). The title originated with an older term for MPs, provosts, from the Old French prévost. While a provost marshal is now usually a senior commissioned officer, they may be a person of any rank who commands any number of MPs; historically, the title was sometimes applied to civilian officials, especially under conditions of martial law, or when a military force had day-to-day responsibility for some or all aspects of civilian law enforcement. A provost marshal may also oversee security services, imprisonment, fire/emergency services and ambulances.

Provosts are military police (MP) whose duties are policing solely within the armed forces of a country, as opposed to gendarmerie duties in the civilian population. However, many countries use their gendarmerie for provost duties.