Crostau (German pronunciation: [ˈkʁɔstaʊ]; Upper Sorbian: Chróstawa, pronounced [ˈkʁʊstawa] ) is a village and former municipality in Upper Lusatia in the Bautzen district of eastern Saxony in Germany. It became part of the municipality of Schirgiswalde-Kirschau on 1 January 2011.