Kluczbork County is a unit of territorial administration and local government (powiat) in Opole Voivodeship, south-western Poland. It came into being on January 1, 1999, as a result of the Polish local government reforms passed in 1998. Its administrative seat and largest town is Kluczbork, which lies north-east of the regional capital Opole. The county also contains the towns of Wolczyn, lying west of Kluczbork, and Byczyna, north of Kluczbork.