A prefecture (from the Latin Praefectura) is an administrative jurisdiction or subdivision in any of various countries and within some international church structures, and in antiquity a Roman district governed by an appointed prefect.

Prefecture most commonly refers to a self-governing body or area since the tetrarchy when Emperor Diocletian divided the Roman Empire into four districts (each divided into dioceses, grouped under a Vicarius (a number of Roman provinces, listed under that article), although he maintained two pretorian prefectures as an administrative level above the also surviving dioceses (a few of which were split).

As canon law is strongly inspired by Roman law, it is not surprising that the Catholic Church has several offices under a prefect. That term occurs also in otherwise styled offices, such as the head of a congregation or department of the Roman Curia. Various ecclesiastical areas, too small for a diocese, are termed prefects.

In Brazil, the prefecture (prefeitura in Portuguese) is the Prefeitura Municipal, home to the Executive of a city and to the mayor's office.