Kościelniki Średnie (German: Mittel-Steinkirch) [kɔɕt͡ɕɛlˈniki ˈɕrɛdɲɛ] is a village in the administrative district of Gmina Leśna, within Lubań County, Lower Silesian Voivodeship, in south-western Poland.

It lies approximately 5 kilometres (3 mi) north of Leśna, 6 kilometres (4 mi) south of Lubań, and 123 kilometres (76 mi) west of the regional capital Wrocław.