Kosztowy (German: Kostow) is a quarter of the city of Mysłowice in the Silesian Voivodship of Poland. The formerly independent municipality is approximately 4 km south the city centre of Mysłowice, close to the neighbouring city of Imielin. In the course of a major re-organisation of municipal borders in Upper Silesia it was incorporated into Mysłowice together with Wesoła and Dziećkowice. It has an area of 5,17 km2 and in 2012 had a population of 3,480.