Kostkowice [kɔstkɔˈvit͡sɛ] is a village in the administrative district of Gmina Kroczyce, within Zawiercie County, Silesian Voivodeship, in southern Poland. It lies approximately 3 kilometres (2 mi) north of Kroczyce, 15 km (9 mi) north-east of Zawiercie, and 56 km (35 mi) north-east of the regional capital Katowice.