Its history dates back probably to the late 14th century, ending in 1837.
In the 15th century, when Lelow County was part of Kraków Voivodeship, its total area was almost 2,500 square kilometres (970 sq mi).
Among towns that belonged to it were Zawiercie, Myszkow, Czestochowa, Klobuck and Krzepice.
The first known starosta of Lelow County was Zbigniew of Brzezie, mentioned in documents from 1408.
The county belonged to Kraków Voivodeship until the Partitions of Poland.