Prefect is a magisterial title of varying definition, but which, basically, refers to the leader of an administrative area. It may also refer to:

• Prefect (France), (French: préfet), is the French state's representative in a department or region
• Prefecture of Police, (French: Préfecture de police), headed by the Prefect of Police (Préfet de police), is an agency of the Government of France
• Maritime Prefect, a servant of the French State who exercises authority over the sea in one particular region (a Préfecture maritime)
• Prefect of Saint Pierre and Miquelon, the local representative of the President of France and in effect the Governor or Executive officer of the territory

• Urban prefect praefectus urbanus or praefectus urbi, was prefect of the city of Rome, and later also of Constantinople
• Praetorian prefect, was the title of a high office in the Roman Empire; originating as the commander of the Praetorian Guard

• Apostolic prefect (or prefect apostolic) is a Roman Catholic priest who heads an apostolic prefecture, a missionary area where the Catholic Church is not yet sufficiently developed to have it made a diocese

• Prefect (Romania), an official of the national government assigned to each county
• Ford Prefect, line of British cars produced by the UK division of Ford Motor Company
• Ford Prefect (character), character in The Hitchhiker's Guide to the Galaxy
• HMS Prefect (Z263), was a net laying ship for the Royal Navy during the Second World
• Slingsby Prefect, a 1948 British modernisation of the 1932 single-seat Grunau Baby glider
• Grob G 120TP, an aircraft which in British service is called the Prefect.
• The Prefects, a British punk band.