Wieluń County (Polish: powiat wieluński) is a unit of territorial administration and local government (powiat) in Łódź Voivodeship, central Poland.

It came into being on 1 January 1999, as a result of the Polish local government reforms passed in 1998.

Its administrative seat and only town is Wieluń, which lies 88 kilometres (55 mi) south-west of the regional capital Łódź.

The county covers an area of 927.69 square kilometres (358.2 sq mi).

These are listed in the following table, in descending order of population.