Kwidzyn County (Polish: powiat kwidzyński) is a unit of territorial administration and local government (powiat) in Pomeranian Voivodeship, northern 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 Kwidzyn, which lies 73 kilometres (45 mi) south of the regional capital Gdańsk.

The only other town in the county is Prabuty, lying 18 km (11 mi) east of Kwidzyn.

The county covers an area of 834.64 square kilometres (322.3 sq mi).