Radziejów County (powiat radziejowski) 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 Radziejów, which lies 45 km south of Toruń and 64 km south-east of Bydgoszcz. The only other town in the county is Piotrków Kujawski, lying 10 km south of Radziejów.
The county covers an area of 607 km2. As of 2019 its total population is 40,546, out of which the population of Radziejów is 5,578, that of Piotrków Kujawski is 4,456, and the rural population is 30,512.
Radziejów County is bordered by Aleksandrów County to the north, Włocławek County to the east, Koło County and Konin County to the south, and Inowrocław County to the north-west.
