Nysa County (Polish: powiat nyski) is a unit of territorial administration and local government (powiat) in Opole Voivodeship, south-western Poland, on the Czech border.

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 Nysa, which lies 48 kilometres (30 mi) south-west of the regional capital Opole.

The county covers an area of 1,223.87 square kilometres (472.5 sq mi).

The county is subdivided into nine gminas (five urban-rural and four rural).