Sępólno County (Polish: powiat sępoleński) is a unit of territorial administration and local government (powiat) in Kuyavian-Pomeranian Voivodeship, north-central 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 Sępólno Krajeńskie, which lies 49 km (30 mi) north-west of Bydgoszcz and 86 km (53 mi) north-west of Toruń.

The county covers an area of 790.86 square kilometres (305.4 sq mi).

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